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Kelly

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  1. Preparing your Pond for Spring Author: Adrienne Dodge First published Aquarium World August 2013 Yes - it is winter and no one feels much like going outside on a cold damp or frosty day, much less do anything about their pond, but if you take a little time now you will be rewarded with a pond that requires a lot less effort come Spring to make it look sparking and clean. Photo Credit: Caryl Simpson Most pond keepers notice that their ponds experience an increase in algae once early Spring (which is not really that far away) arrives. The cause of this is the pond plants ie the beautiful water lilies, which gave so much pleasure over summer have died down in the water or become dormant. If there are lots of dead leaves on the bottom of your pond combined with fish waste rotting over winter, the algae is going to feed on the nutrients when the days start to lengthen and get a good head start over new plant growth. If you remove the dead and rotting leaves and debris off the bottom of your pond over the winter you are going to slow this process down. Leaves can be removed with a skimmer type net that has a square end which enables you to push it across the bottom of the pond. There are also pond vacuums available for this purpose however they require high-pressure cold water for them to be effective. You can also rearrange decorative rocks and make plans for new plantings in the area around the pond while you are working away. A water feature is a popular addition to a pond and August is a good time to clean it out. Completely emptying it and removing all the sludge and debris from inside it with a scrubbing brush will make it look like new! Once the weather begins to warm and all signs of frosts have passed then it is time to turn your pump back on (if you live in the colder areas of NZ and turn it off for the winter). You can begin to feed your fish again albeit sparingly once the water temperature has reached a constant 10 degrees Celsius increasing the amount you feed back to your normal feeding routine when the temperature of your pond reaches 15.5 degrees Celsius. If you chose not to venture out in the colder weather to do some remedial clearing out of your pond now may be the time for you to decide whether or not you need to do a complete water change. This is not desirable as it will affect the balance of the pond and upset your algae control but if your pond is full of rotten leaves and sludge it may be your only option. This is the method I suggest if you are going down this route – · Pump or place water from your pond into a large bucket, tub or container · Place your fish in this container and cover it with netting to prevent fish jumping out · Pump out as much water from your pond as you can and remove any potted plants. · Use a dustpan and brush to remove all the sludge · Refill your pond being sure to remove chlorine with a de-chlorinator (pond de-chlorinators are available and go a long way) · Add some of the de-chlorinated water to the container your fish are in and wait half an hour (about 1/3 of new water to the existing water) · Return your fish to the pond along with the water from the container they were in · Return your plants Now is also the time to fertilise your plants. Plants such as water lilies require fertilizer every four weeks during the growing season. If your water starts to turn slightly green turn on your UV sterliser if you have one. N.B. There are other options available aside from a UV sterilizer to help you keep your pond water clear, such as algae removers and barley extracts, however the UV sterilizer is the most reliable method of removing green water and keeping it clear. Your filter is also going to require cleaning. If you have a pre filter you will most probably need to check and clean this weekly. If you have a biological filter this will need cleaning when the flow reduces due to all the debris accumulating in it. Clean the filter sparingly by removing only enough debris to return the flow to normal. Photo Credit: Caryl Simpson Happy Pond Keeping!
  2. Kelly

    Torrentfish

    Torrentfish (Māori: Panoko) Author: Darren Stevens Excerpt from Bluecod and Torrentfish first published in Aquarium World May 2014 Torrentfish (Photo credit Charles Fryett) As their European name suggests, torrentfish (Cheimarrichthys fosteri) often live in swift flowing rapids. They are superbly adapted to life in fast water with a flattened head and very large pectoral fins, which help to keep them on to the bottom, and a powerful square tail to enable them to dart from stone to stone. Torrentfish are a relatively small (commonly to 100-125mm) typically grey to grey-brown fish with a dark band through the eyes, three diagonal dark bands on the body, and a fourth just in front of the tail. Their cryptic colouration and fast water habitat means they are seldom seen but they are widely distributed, and at times common, in low elevation stony rivers and streams throughout mainland New Zealand. Torrentfish eat mainly aquatic insects and they are thought to move to quieter waters at night to feed. Their life history is not well understood but adult female torrentfish tend to live further upstream than males so they must migrate to spawn. They are thought to spawn in freshwater near the coast and the resulting larvae carried out to sea by the current. Over spring and summer small juvenile torrentfish (20-25 mm) move into river mouths where they are sometimes captured by whitebaiters. Torrentfish x 2 (Photo credit Charles Fryett) These delightful fish can be kept in freshwater native aquaria providing a strong current is provided. There is excellent information on how to keep torrentfish in ‘The New Zealand Native Freshwater Aquarium’ by Stella McQueen. References McDowall, R.M. (2011). Ikawai. Freshwater Fishes in Maori Culture and Economy. Canterbury University Press. McQueen, S. (2010). The New Zealand Freshwater Aquarium. Wet Sock Publications. McQueen, S., Morris, R. (2013). A photographic guide to the freshwater fishes of New Zealand. New Holland Publishers (NZ) Ltd. NIWA Atlas of NZ Freshwater Fishes (https://www.niwa.co.nz/freshwater-and-estuaries/nzffd/NIWA-fish-atlas) © This item may not be reproduced without written permission
  3. Kelly

    Brown Bullhead

    The brown bullhead - our very own catfish pest Author: Darren Stevens First published in Aquarium World February 2014 brown bullhead © Noel Burkhead Although many aquarists will have a common bristlenose or Corydoras catfish in their tropical tanks there are no native freshwater catfish (Siluriformes) in New Zealand. In contrast, our Australian neighbours have about 18 freshwater catfish species. We do however have an introduced species, the brown bullhead (Ameiurus nebulosus) a stocky dark brown to greenish-olive catfish with 4 long whisker-like barbels, speckled with gold, pale olive, and grey. Brown bulheads are generally found in slow flowing, often weedy, streams and around the sandy shallow margins of lakes and lagoons. In New Zealand they commonly grow to 30cm but have been reported to grow to about 45cm and 2kg. They eat a wide range of food including freshwater insects, snails, crustaceans including koura, plant material, detritus, and small fish. They are a problem in our waters as they compete with, and eat, native species, including small native fish and koura. They also reduce water quality by stirring up mud. In New Zealand brown bullheads are not well studied although they appear to be fast growing, reaching 8cm in their first year, and 33cm by their fourth year, and they may live for up to 8 years. They mature at age 2 or 3 (at about 180-200mm TL) and pair up and spawn during spring. They lay several hundred to over 6000 golden eggs in a shallow depression in mud or sand. Initially both sexes guard the eggs and young but as the young develop it is generally the male that will guard the young for several weeks. Brown bullheads were introduced to New Zealand from California in 1877 and initially became established in the lower Waikato River and in Lake Mahinapua near Hokitika. They are very adaptable and are able to survive for long periods out of water. Unfortunately this makes them easy to accidentally transfer to new waterways in fyke nets or on boat trailers, and they are now reported from a number of waterways including the Whanganui River, Ruamahanga River, and Lake Taupo. At times they can very abundant with a single overnight fyke set in Lake Taupo catching 639 catfish. To help prevent further spread if you catch a brown bullhead you must kill it immediately. The penalty for possessing a live bullhead catfish is $750. References: McDowall, R. M. (1990). New Zealand Freshwater Fishes: A natural history and guide. Heinemann Reed, Auckland. Brown Bullhead Catfish – Code of Practice Effective from 1 October 2007. http://www.fish.govt.nz/NR/rdonlyres/333F2B8C-6808-4DD7-868A-B7100F71DDE8/0/Brown_Bullhead_Catfish_Code_of_Practice.pdf Barnes, G.E.; Hicks, B.J. (2001). Brown bullhead catfish (Ameiurus nebulosus) in Lake Taupo. In: Department of Conservation 2003. Managing invasive freshwater fish in New Zealand. Proceedings of a workshop hosted by the Department of Conservation, 10-12 May 2001, Hamilton. xiv +174 p. © This item may not be reproduced without written permission
  4. Kelly

    Native Glass Shrimp

    Native Glass Shrimp Author: James Cooper First published in Aquarium World February 2014 Parataya curvirostis Max Size: 9cm Temperature: 5 – 26°C pH: 6.5-8.5 (high reading due to marine larval stage, 6.5-7.5 best for adults.) These peaceful detritivores are great as a clean up crew for an aquarium, especially for their ability to consume Black Beard Algae. Quite common New Zealand wide, even on Stewart Island, they can also penetrate inland quite far but their full range has never been investigated. This shrimp has a marine larval stage so is unable to be bred in the home aquarium without specialised equipment. They are easy to collect by sweeping a net through stream-side vegetation. Glass shrimp are less common in waterways that have been infested with Gambusia. Sex is determined by size, the larger specimens over 5cm being female. Please release all larger specimens that have been caught to ensure future generations of shrimp. They are quite happy in tropical tanks as long as the temperature does not rise above 26°C at which point a very high mortality rate is recorded. They are very sensitive to ammonia so should be added to mature systems. There are several different colour morphs recorded such as black, green or red, which seem related to diet but in the wild they are normally a clear yellow colour with slight coloured speckling (colour depends on locality of capture). Lifespan is estimated to be about 2 years (Carpenter 1983) and they die after approximately 6-8 months as a female. References Alan Carpenter (1983): Population biology of the freshwater shrimp Paratya curvirostris (Heller, 1862) (Decapoda: Atyidae), New Zealand Journal of Marine and Freshwater Research, 17:2, 147-158 © This item may not be reproduced without written permission
  5. How-to Get Rid of Algae InstantlyAuthor: Jennifer Hamlin First Published in Aquarium World August 2013 While this may sound like a ‘magic pill’ for everybody’s worst aquarium nemesis, it really is not. Algae grows whenever there are available nutrients and light so solving the cause of the problem is a more complex issue, however, it is possible to quickly improve the appearance of plants and fixtures in the aquarium with a simple treatment. The treatment for quickly eliminating algae on plants and surfaces involves chlorine bleach (sodium hypochlorite) which is poisonous to aquatic life. Bleach must never be used in a living aquarium, or anywhere near living fish. Bleach can be used on plants, fixtures, ornaments, rocks, and wood which have been safely removed from the tank. Once treated these can be rinsed well and safely returned to the living tank with no ill effects to the fish or bacterial filtration. To carry out this treatment, carefully follow the instructions below: Get some bleach – Chose a quality plain bleach solution. You get what you pay for. Cheaper brands often have much lower concentrations so they may not be as effective. Bleach also ages with time and the chlorine diffuses out of the liquid so an old bottle on the shelf will no longer have the same effectiveness of a freshly produced bottle. Prepare yourself and the environment – Concentrated bleach will discolour and eat away fabrics like clothing, carpet and furnishings as well as erode some metals. Prevent damage by preparing the solution in an environment that can handle some splashes if they occur. Wear white clothes, or clothes that you don’t mind getting damaged and wear gloves. Open a window for ventilation if the smell bothers you. Measure out 20mls (4 teaspoons) of bleach and add to a plastic bucket filled with about 1 litre of lukewarm or cool water. The amount is not exact and depends on the quality of the bleach. The more concentrated bleach you use, the faster it will kill the algae, however, if you use too much (e.g. more than 20%) it will risk damaging porous ornaments and fixtures and will certainly damage living plants. Take care and only use the minimum amount needed to do the job. Choose the fixtures, ornaments, and plants that you wish to treat and remove them from the tank. Rinse off any organic matter like mulm, fish food or rotting plants. Place the items into the bucket of diluted bleach and make sure they are submerged under the surface of the solution. Leave them in the solution for the time suggested in the chart below. Once the allotted time has passed, remove the items from the bucket and rinse well under a running tap. The solution will quickly rinse off but if you are worried, you can additionally submerge them in a bucket of water with added de-chlorinator which will neutralise any remaining bleach. The items can now be safely added back to the tank! Recommended exposure times of bleach-solution to get rid of algae on surfaces Ornaments & fixtures: Wood, rocks, plastic aquarium ornaments - up to 5 minutes Filter pipes, glasswear – up to 5 minutes Rubber fittings, sponges – up to 2 minutes Plastic plants – up to 5 minutes Silk plants - not recommended Aquatic plants (living):* Anubias species – up to 5 minutes Cryptocoryne – up to 3 minutes Echinodorous – up to 3 minutes Rotala sp.– up to 2 minutes Ludwigia – up to 2 minutes Tiger lotus – up to 2 minutes All mosses – not recommended Bolbitis sp. – not recommended Twisted Valisinaria – not recommended Indian fern – not recommended *Living plants that have damaged leaves will not hold up well to bleach so it is best to remove these leaves beforehand, minimize the bleaching time, or avoid bleaching the damaged leaves altogether. Many other plants can be bleached, if only for a minute or less which will kill the single-cells of the algae. Fragile soft-leafed plants are less tolerant of bleach so take care if trying this treatment on them. If the bleach solution is particularly concentrated, algae can immediately turn white. Some species of algae will turn pink or brown within minutes to hours after bleaching and some alage will just disintegrate once the ornament is placed back into the tank. In a day or so, all evidence of the alage will be completely gone! After 24 hours After 2 days © This item may not be reproduced without written permission
  6. Kelly

    The pH probe

    The pH Probe Author: Paula Brooksby First published in Aquarium World August 2013 The pH probe is a useful piece of equipment used to measure the acidity or alkalinity of water in the aquarium. The probe itself contains a glass bulb that comes in contact with the water. It is the thickness of this glass bulb that affects the measurement and hence the accuracy; therefore, anything that damages the glass should be avoided (scratches, exposure to chemicals, algae, etc.). The glass bulb is special in that it can sense acid/hydrogen ions. When the bulb is exposed to water, the alkali ions in the glass bulb exchange with hydrogen ions in the water and this process generates a potential (voltage) difference. It is this potential difference that is measured and converted to a pH value that we understand when measuring our water acidity or alkalinity. Inside the body of the glass bulb in most typical combination pH probe units there are two electrodes separated by a junction. These two electrodes include a measuring electrode which gets immersed in aquarium water and a reference electrode sealed in its reference solution (whose potential is always constant). The potential generated at the junction of these two electrodes is a consequence of the hydrogen ion concentration in the aquarium water and the difference between them gives the measurement of the aquarium water. The junction between these two electrodes can become blocked by particulates and occasionally some metal ions can precipitate in the junction. If this occurs the electrode needs to be soaked in warm tap water to dissolve the material and unblock the junction. In order to operate correctly, the pH electrode needs to be kept moist at all times as this keeps the glass hydrated. Hydration is required for the ion exchange process. Ideally the electrode should be kept in a buffered solution at either pH 4 or 7. It should never be stored in alkaline pH (as this can dissolve the glass) or distilled or deionized water (as this causes migration from the reference solution). If the pH electrode dries out it is best practice to recondition the glass by placing it in some tap water for 30 minutes prior to usage. All pH electrodes can run down with time and use (just like a battery) and as the electrode ages there are changes to the glass resistance. This in turn changes the electrode potential and affects accuracy of the results which is why they need regular calibration to correct for this gradual and continual change. It is important to read the instructions specific for each meter but generally the pH electrode should be calibrated before each use and standard buffer solutions should always be used. Buffer solutions or tablets can be purchased for this purpose. Standard buffers come in three pH values: 4, 7 and 10. buffers should be stored away from heat and in tightly sealed containers. Always use freshly poured solutions for each calibration. There are two types of calibration: one-point calibration (done at a single pH point provided that point is close to the expected pH of the tank water) or dual calibration (between two range points) which gives greater accuracy. One-point calibration: Calibrate the meter using only one buffer. The value of the buffer should be close to the anticipated sample pH value. Two-point calibration: Calibrate the meter using two buffers. One buffer is pH 7 and the other is pH 4 or 10. Choose the second buffer based on whether you are measuring an acidic solution (chose the pH 4 buffer) or an alkaline solution (choose the pH 10 buffer). Dual calibration method: If there is a temperature setting, the meter must correspond to the temperature of the buffers. Place electrode into fresh pH 7 buffer at room temperature. · Adjust meter to read 7.00 using the zero offset dial (for the one-point calibration method, at this point the electrode would be placed into a solution with a known pH value e.g. pH 7). Withdraw the electrode from the solution and rinse with water. · Wick the electrode dry by dabbing it briefly against a clean paper towel (do not rub dry as this can cause a static voltage to setup between the two electrodes). · Place the electrode into the second buffer solution (pH 4 or 10) and adjust the meter with the slope or gain controls to make it read the same as the known buffer (refer to manufacturer instructions if needed). · The pH electrode is now calibrated and ready to use. A pH electrode is designed to operate at room temperature, which is nominally given as 25 °C. If probes are to be used at other temperatures, then the measurement observed needs to be corrected for the temperature variation. Tables are available if precise measurements are necessary, otherwise, when the temperature is anything other than 25 °C and the pH is anything other than 7, the correction is: 0.03 pH error/pH unit/10 °C. For example, in going from 25 to 35 °C and pH 7 to pH 4, the error is +0.09 - generally not a concern for most practical aquarium applications. After each use, rinse the electrode with water and store it in soft (low salt) acidic solution. Commercial soaking solutions are available or you can make your own by mixing 1 M KCl (~0.75 g / 10 mL) adjusted to pH 4 with a few drops of concentrated acid. The level of filling (if this is an option for your electrode) should be kept at least 2/3 full and be open during use. The life-span of a typical pH probe depends on the conditions in which they are used and the care with which they have been stored. For a probe that is only used occasionally and which is stored properly, it can continue to operate for a number of years but a probe in continuous use may last as little as 6 months. Even electrodes that are never used still age and deteriorate with time. When an electrode is failing it can typically be characterized by sluggish response, erratic readings or a reading that does not change. When this occurs the electrode can no longer be calibrated. Reference: http://www.omega.com/Green/pdf/pHbasics_REF.pdf ©This item may not be reproduced without written permission
  7. Kelly

    Bullies

    Bullies Author: James Cooper First published in Aquarium World August 2013 Introduction Attractive, tough and full of character, Bullies are a hardy and easy to obtain New Zealand native fish. The name bully is short for Cock-a-bully, a name given to these fish by the early European settlers; it is thought the name is a mispronunciation of ‘Kokapuru’ the Maori word for small fish. Cran's bully male (Photo credit Charles Fryett) Bullies live in a wide range of habitats throughout New Zealand and most varieties are common, although this status is being threatened by the spread of predatory Brown Trout and invasive pest species such as Gambusia as well as the reduction of habitats. Most species are endemic to their specific habitat but occasionally species can be found co-habitating in prime areas. Bullies can change colour depending on season, mood, and breeding behaviour. Colouration can even vary within the same species for specimens found in different environments around the country so it can be a real challenge to definitively identify them. Bullies are generally hardy and easy to obtain, living for around 3- 5 years, and they have an inquisitive personality so are the perfect candidate for someone interested in having a go at keeping New Zealand natives. Setting up an Aquarium for Bullies Bullies are cold water fish and need to be kept below 20°C to be comfortable. The best way to achieve this is to keep an eye on the room temperature and if it is nearing 25°C, a few ice cubes, floating a frozen bottle of water, or a fan directed at the water’s surface can bring the temperature down. If you are serious about keeping New Zealand natives it is wise to consider a chiller unit and although rather expensive, they allow you to keep the tank consistently cooler which will ensure you have happy, healthy and therefore beautiful fish. Most bullies are medium sized fish (10-25 cm) so they are one of the best native species for smaller tanks. A good minimum size tank for 3-4 adult 10 cm bullies is a standard 2ft tank (600mm x 300mm x 300mm) however they are bottom dwellers so it is more important to have a large footprint rather than a lot of height in the water column. As is standard for all fishkeeping, the bigger the better and a larger tank will allow you to keep water parameters more stable as well as allowing the introduction of other New Zealand native mid-water fish such as Inanga (Galaxias Maculate) or Smelt (Retropinna retropinna or Stokellia anisodon). The tank substrate should be fine sand or gravel substrate and include lots of rocks, driftwood and other areas of cover for the fish to reduce stress. Tank lighting is not essential for Bullies as they are normally nocturnal in the wild and bright lighting will usually make them run for cover. To allow for good viewing of the aquarium, dim lighting can be used and as they get used to this, they will come out more often. Collecting Bullies in the Wild Taking fish from the wild is a big responsibility. Once a fish is removed from a native habitat, it is illegal to release it back into the waterway (this also includes plants and invertebrates) so you must be prepared to care for it before you go out collecting. Most native fishes are nocturnal so catching them involves venturing out in the evening for spotlighting in waterways. To capture Bullies, it is best to use a two-net approach, with one large net slowly drawn up behind the fish and another used to scare the fish downstream into the waiting net. A good quality headlamp is a must in this situation. Another approach is to set bait traps with a bit of bread into a quiet pool or along the river bank or lake; these traps can be purchased at most fishing tackle stores. Night time spotlighting (Photo credit Charles Fryett) Once captured, it is important to identify the species. Juveniles (around the 3-5cm mark) are the best as they will adjust to the home aquarium a lot better than an older specimen. Once you have your fish home it is important to acclimate the fish very slowly. The easiest way to do this is to use the ‘drip’ method favoured by marine fish keepers. This is accomplished by placing the fish in a bucket below the tank, and using a length of standard air-hose. Start a siphon down to the bucket, clip or a loose knot in the hose will allow you to control the flow of water - the aim is for the water to flow at around one drip per second. Once the bucket is full you can net out the fish and add it to the tank. It is best to avoid adding the water from the bucket as it may contain high levels of fish waste. Behaviour Most bullies are rather peaceful and tend to be friendly to other tank mates except around breeding time, even then most squabbles are harmless. They will however eat anything that they can swallow whole so this must be taken into account when choosing tank mates. Apart from this, they are very well behaved and inquisitive, known for spending a lot of their time watching the outside world and enjoying vantage points on which to perch for a better view, often pushing each other out of the way to get the best spots. Feeding Most bullies will transfer onto a diet of standard dry food quickly, however it is best to use a sinking pellet type rather than a flake as it holds together better and causes less pollution in the tank. Frozen bloodworms are useful as a treat but should not be used as a staple diet as they are nutritionally lacking. Another good alternative is a prepared food with ox heart and a variety of vegetables, there are a range of recipes out there and a quick search will provide you with one you can use. The benefit of this food is that you can control what goes in to it and ensure your fish get a balanced diet. If available, live food is a great option, there is a variety of easily cultured foods available such as daphnia, whiteworms, blackworms, maggots or earthworms which provide a lot of nutritional value as well as promoting the fish’s natural hunting behaviour. Cran's bully eggs 20+ days (Photo credit Charles Fryett) Breeding All bullies are cave spawners. Normally during spring or summer the male will set up a territory within a cave-like structure, normally the side under a rock or log. The male adopts a dark colouration, almost black in some species. The female will deposit a number of eggs inside the cave and then leaves so the male can guard the nest until the larvae hatch. This takes up to several weeks, the time is temperature dependant. Some species spend their larval stage around the place they were born; some migrate down to sea and return once they have reached a certain size. One (the Tarndale Bully) even has free swimming pelagic larvae. The only types that can be successfully bred in the home aquarium are the Upland bully and the Crans bully. Common Bully - possibly male (Photo credit Charles Fryett) Common Bully Gobiomorphus cotidianus Found throughout NZ and the most common bully as its name suggests, it is found in lowland areas around coastal rivers and lakes. It is normally not found far inland as it is not known to be a great climber like some of its couterparts. This bully is one of the best for beginners due to its amazing hardiness - this is not to say it should be mistreated as a well kept specimen is a sight to behold. Grows up to 15cm, matures at around one year old and lives for 4-5 years. It is a sea run spawner but there are landlocked populations that complete their entire lifecycle in fresh water. Giant Bully (Photo credit Charles Fryett) Giant Bully Gobiomorphus gobioides The largest of the native Bullies gets to a length of 24 cm and is commonly found in the lower reaches of rivers and even into brackish water of estuaries. They rarely travel far upstream from their home habitat. Juvenile Giant Bullies and Common Bullies are hard to distinguish from each other; the rule of thumb is that Common Bullies have seven spines in their first dorsal fins and Giants have only six. Another clue is that the lower jaw of Giant Bullies extends past the top lip where as in Commons the jaws tend to be more equal. Giant Bullies can be a bit aggressive to other smaller tank-mates and they also like to hide under overhanging banks and in heavy cover so they not only require a larger aquarium than other bullies, but they also appreciate adequate cover and hiding places. Red fin bully (Photo credit Liam Winterton) Redfin Bully Gobiomorphus huttoni The jewel of New Zealand native fish is the spectacularly coloured Redfin Bully where males of the species have brightly coloured finnage and variable body colouring with bright yellows, reds and iridescent greens. During breeding they will turn a solid black with a bright green edge to their first dorsal fin. Females have fewer colours but still have the diagonal facial stripes that are a tell-tale sign of this species. They are a smaller bully only reaching a maximum of 122mm (females are smaller growing) so are perfect for the smaller aquarium or species only tank. They are found NZ wide and are well accomplished climbers found well inland even past significant barriers such as waterfalls. Unfortunately, they are a sea-run2 fish so have not been successfully bred in the home aquarium. Bluegill bully (Photo credit Stella McQueen) Bluegill Bully Gobiomorphus hubbsi This little stunner is an inhabitant of faster flowing water and loves a strong current to play around in. Bluegill Bullies have a longer more streamlined body-shape that is perfectly adapted for living in fast flowing rapids of new Zealand rivers. The Bluegill Bully is also a smaller growing species, only reaching 93 mm. An aquarium for these beauties requires a strong water flow and a lot of surface movement to ensure high amounts of oxygen like those found in its natural habitat. With careful placement of stones you can create calmer areas for the fish to rest and feed right. Found New Zealand wide, the Bluegill has a sea-run larval stage and are very short lived, living only to around 2 or 3 years maximum. Cran's Bully male in breeding colours (Photo credit Charles Fryett) Cran's Bully male with large female (Photo credit Charles Fryett) Cran's Bully Gobiomorphus basalis Short and squat, these fish can only be described as cute. Crans Bully bodies are mottled with sandy browns and olive greens, the males sport a bright pink/orange margin to their first dorsal fin. As the males age their heads become more blunt and bulbous. They are found mainly in inland rocky streams throughout the North Island except in the Bay of Plenty region from Waihi to East Cape. These Bullies are one of the landlocked bullies that can be successfully bred in the home aquarium. It is one of the most common species in the North Island and grows to a maximum of 92 mm. Upland Bully (Photo credit: Stella McQueen) Upland Bully Gobiomorphus breviceps. A distinctive bully with a lighter grey/brown base colour than most of the more coastal bullies and irregular brown patches and orange/brown spots. Males are stouter and have a blunter head that gets more blunt with age and a orange fringe to the first dorsal fin and a light orange patch at the base of the pectoral fin. Females lack the orange. As its name suggests it is found in upland areas throughout the South Island and in a few rivers and streams of the southern North Island. It is a fully freshwater species and can be bred in the aquarium. This is a slightly larger species growing to a maximum of 135 mm. Tarndale Bully Gobiomorphus alpinus Here more out of interest than for actual keeping, the Tarndale Bully is NZ's smallest bully with a maximum recorded size of 75 mm. It is also interesting in that its larval stage, although freshwater it is also pelagic1. It is only found only in the Lakes of Tarndale Station in Molesworth, near Marlborough and in the upper Clarence river system and Wairau river. The Tarndale Bullis are slender and rather big-headed but otherwise hard to distinguish from the Common Bully. They are not technically protected, as are none of our living native freshwater species, but considering their rarity, it would be considered ethically wrong to attempt to collect it without proper consent and knowledge of the relevant authorities. Being only found on private property, trespassing laws would also apply. 1 Pelagic fish live near the surface or in the water column of coastal, ocean and lake waters, but not on the bottom of the sea or the lake. http://en.wikipedia.org/wiki/Pelagic_fish 2 Sea run – Spawning takes place in fresh water and after hatching the larvae are swept out to sea. As juveniles they return to fresh water where they spend their adult lives. Further reading on Bullies: The Reed Field Guide to New Zealand Fishes; R. M. McDowall; 2000 Ikawai – Freshwater fishes in Maori culture and economy; R. M. McDowall; 2011 The New Zealand Native Freshwater Aquarium; S. McQueen; 2010 A Photographic Guide to Freshwater Fishes of New Zealand; S. McQueen; 2013 FNZAS Native Freshwater Fishes; FNZAS/C. Fryett; To be published © This item may not be reproduced without written permission
  8. Optimising Plant Growth and Minimising Algae Author: Jennifer Hamlin Photo credit: Aakash Sarin Nutrients The main nutrients for plants are Carbon, Nitrate, Potassium, Phosphate, Iron and Magnesium. Those are usually known as macronutrients. The micronutrients are all of the other trace minerals just like those found in your own multivitamin tablet. Plant Growth Some key points about plant growth. 1. When plants are growing optimally, they use up nutrients in the water column. 2. The more light they have, the more plants will seek nutrients. 3. Without nutrients the plant growth will be limited. Light is a key factor to growth demands. If the lights are on too long, the plants will use up the available nutrients and leave behind whatever they can't use. Plants have a limited ability to adapt quickly to changes in nutrient and light levels. Plants require enzymes like rubisco to produce energy for growth and when conditions change the plants' enzyme levels also change, but it takes time. In other words, if you suddenly add a lot more light and a lot more nutrients, the plants will not be able to use it until they adapt their enzyme levels to the new conditions. AlgaeAlgae is not fussy about nutrients and will use whatever is available; it can also adapt much more quickly than plants so it can easily take over when conditions are right. if plants are growing well, they will strip the nutrients from the water column faster than algae can and this will prevent algae from getting a foothold. There are certain things that can cause alage. One of the biggest culprits is fluctuating carbon (CO2) levels. More than other nutrients, carbon can be challenging to add to the tank and this can result in fluctuations. Like any nutrient, fluctuating carbon levels will prevent the plants from growing well and algae are right there ready to take up the opportunity. Another main cause of algae are spikes in other nutrients that are not as quickly utilised by plants, such as ammonia. Ammonia is produced by fish respiration, waste products and decaying organic material like dead plants and plants. Even a cycled tank can have a temporary ammonia spike. Algae can quickly be controlled by adjusting the nutrients you are dosing. This works surprisingly well. For instance, if you are getting black beard algae, increase the carbon/CO2; if you are getting green spot algae, increase the phosphate levels. EI dosingEstimative Index dosing is a method of fertilising developed by plant guru Tom Barr. It is based on the principle of ensuring that nutrients are always available to the plants so that they can grow optimally when the lights are on. This means that nutrients are not the limiting factor for growth. A typical target range for EI dosing in your tank is:CO2 25-35 ppmNitrate (NO3) 10-30 ppmPotassium (K+) 10-30 ppmPhosphate (PO4) 1.0-2.0 ppmIron (Fe) 0.2-0.5ppm or higherGH range 17-40 ppm or higherNotice that carbon is a vital nutrient. This is provided in the form of liquid carbon or CO2. The ranges above can be achieved in a low or high tech tank, the difference being the speed at which the plants will use up the nutrients (and thus the frequency that you need to dose the tank). Either way, aim to add micronutrients at the same frequency that you add the macronutrients above, they will not be used up as fast as macronutients but you don't want any deficiencies so you need to keep them up as well.The difference between high and low tech setups is just the speed of plant growth (amount of plant biomass that is produced). The only reason to have high light and high nutrients is to have fast growing plants. Fast growing plants are like teenage boys - they need a lot of food. SummarySo, to make a long story short: 1. make slow adjustments when you are changing nutrients, CO2 and light in the tank 2. make sure your lighting level matches the amount of nutrients in the water3. add micronutrients and macronutrients (including carbon) as often as needed to match your lighting levelsEach tank is different in terms of the lighting intensity, photoperiod, filtration, stocking levels and plant biomass so dose rates will vary slightly to achieve the target ranges above. © This item may not be reproduced without written permission
  9. Kelly

    Koi Carp

    Koi Carp Cyprinus carpio Koi carp are an ornamental strain of the common carp native to Asia and Europe. They were introduced to New Zealand accidentally in the 1960’s as part of a goldfish consignment. They contribute to water quality deterioration and are a serious problem in Australia, as well as New Zealand. Description and Life History: Koi carp resemble goldfish except that they have two pairs of barbels (feelers) at the corners of their mouth. They are highly variable in colour, often with irregular blotching of black, red, gold, orange or pearly white. Koi carp are long-lived fish and grow to about 750 mm in length. What damage do they do? The way that Koi carp feed stirs up the bottom of ponds, lakes, rivers muddying the water and destroying native plant and fish habitat. Koi carp are opportunistic feeder, eating insects, spawn, juvenile fish of other species and diverse range of plants and organic matter. They feed like a vacuum cleaner, sucking up everything and blowing out what isn’t wanted. Aquatic plants are dislodged in the process and unable to re-establish. Koi carp cause habitat loss for plants, native fish and waterfowl. Where are they found in NZ? Koi carp prefer still waters in lakes, or backwaters in rivers. They are very tolerant of poor water quality, contributing to water quality decline. Koi carp are widespread in Auckland and Waikato. They are spreading into Northland and they have been found in isolated places in Wanganui, Hawkes Bay and Wellington. Koi carp are not thought to be in the South Island. To help stop their spread a containment area between Auckland and Hamilton was created. In the containment area, recreational fishing is permitted, but all Koi must be killed when caught. Koi carp outside of the containment area are considered a serious incursion and control options will be investigated. Legal Designation: Unwanted organism. Further information can be found here
  10. Kelly

    Gambusia

    Pest FishGambusia (formerly known as Mosquito Fish) Gambusia affinis are small fish introduced to New Zealand in the 1930’s from the Gulf of Mexico to control mosquito larvae but, ironically, they are not very good at it! Their ability to control mosquitoes has been exaggerated and they have become pests in many countries around the world. They are very aggressive fish and will attack fish much larger than themselves. This has lead to them being nicknamed “killer guppies”. Description and Life History:Gambusia is a small fish with a greenish silvery sheen. Mature females grown to 6 cm and males to 3.5 cm. They mature at six weeks old and are unusual because they give birth to live young. This means that only one pregnant female is needed to start a new population. These features allow Gambusia populations to build up to large numbers very quickly. What damage do they do?Gambusia populations quickly expand to out number other species. They attack native fish by nipping at their fins and eyes and prey on their eggs. Whitebait and mudfish species are especially vulnerable to Gambusia, as they inhabit similar habitats. Where are they found in NZ?Gambusia prefers the shallow margins of slow flowing ponds, wetlands and streams especially around aquatic plants. They can tolerate poor water quality and a wide range of water temperatures. Gambusia is widespread throughout Northland, Auckland, Waikato and Bay of Plenty. Isolated populations have been found in Hawkes Bay, Wanganui and Nelson. Native fish such as whitebait, bullies and eels and aquatic invertebrates all feed on mosquito larvae. In addition introduced goldfish and tadpoles and frogs don’t cause as many problems as Gambusia and feed on mosquito larvae. If you have got mosquito problems:Empty containers around your home that contain water (saucers, jars, tyres, paddling pools etc) and clear your guttering. If you have a pond make it as unfriendly to mosquitoes as possible by making the sides steep, having flowing water and planting plants around the edge to shade the water. This will improve your ponds habitat for other species that feed on mosquitoes. Legal Designation:Unwanted organism. Further information can be found here
  11. Shipping fish by mail Adapted from an article by Bill (PegasusNZ) The shipping box You would need a suitable styrene box.. plus a heat pack if the trip is a long one. Some of these 'heat packs' generate heat when rubbed vigorously.. so avoid doing this until the very last moment before you finally seal the box. Others need a continuous supply of air so after the box is sealed it is important to make a small hole in the lid of the box. Very Important Do not feed fish 24 hours prior to sending. Fill the bag with approximately one third water.. then insert an airline from your air pump into the neck of the bag and twist to create a seal. Allow the bag to inflate...then twist the neck of the bag some more and pull out the airline while keeping the bag fully inflated. Fold the neck of the bag over firmly and hold in position with two good strong rubber bands... MINIMUM 100mm (4") allowance for twisting and folding over. There should be no air leaks. Crumple up some newspaper and place in the styrene box, then add the bag or bags, packing each so they can't roll around. Add the heat pad if needed, but don't lay it directly on the pastic bags, just pack it so the heat can circulate. Coldwater Goldfish etc: As above, but ommit the heat pack.. plus one or two fish per bag only... depending on size. Plecos... Spiney Catfish etc: Use Tupperware containers.. one third water.. two thirds air.. plus heat pack in most cases. Adult Swords.. Cichlids etc: One or two per bag.. as above.. depending on size. Adult Angels: ONE per bag always... plus heat pack. Plants Only: Just pack loosly in wet newspaper and place flat in a poly bag. Seal to avoid leakage. Post in a bubble pack type envelope. Another method when packing some of the more fragile type plants... (thanks Cyberfin).. is to place them in a partially inflated plastic bag. The air will cushion them from being crushed. No water except what is on the plant when removed from tank, as sloshing water can damage. If the bag is sealed properly it will remain relatively humid within. Mark the box CLEARLY with the name and address plus postcode... plus LIVE FISH... PLEASE CONTACT ON ARRIVAL.. and phone number if they are being sent to a collection point... like a service station or somewhere. Contact The Person: Contact the person as soon as you send the goods. Inform them which service you have used, the Track and Trace number, and when to expect deliverery.. AND WHERE.. in some cases courier services will not deliver to home addresses.. but will drop parcels at a selected pick up point. If in doubt... DOUBLE BAG ALWAYS Some add a couple of drops of "Stess Coat" for the trip. Some also recommend "Amolock", as it locks up any ammonina into a non toxic form. Take care here and follow the instructions if you use these products. Snails and such can be packed in a simple small strong cardboad box with bit of wet plant.. but they won't need a lot of water.. just a cupful perhaps, and the bag can be much smaller... plus the heat pack will not be needed. Shop Around: Not a lot of carriers will transport fish these days.. and the cost can vary tremendously. Look at paying around $18:00 for a local overnight trip.. and triple that for some areas... but this depends on the carrier. Try Post Haste Couriers... they are pretty good.. but not ALL branches of any courier will handle live stock. © This item may not be reproduced without written permission
  12. What should I feed my tropical fish? Author: Adrienne Dodge First published in Aquarium World August 2013 This is a question that commonly pops up. What you feed your fish is as important as the aquarium conditions you provide for them. For newer fish keepers I have placed a table at the bottom of this article giving some idea of the basic foods to feed the type of fish typically kept by beginners to the hobby. The type of food you feed your fish depends largely on the following - The size of your fish and the size of its mouth - Whether your fish is a herbivore (eats plants), a carnivore (eats animals), or an omnivore (eats both) - Is your fish a surface feeder or a bottom feeder? - Does your fish feed during the day or at night only? It is important to remember that regardless of what type of food you feed to your fish, varying the diet to ensure balanced nutrition is also necessary. There are a huge number of commercially prepared fish foods available that can be used. A lot will depend on your preference and how convenient it is for you to feed it. A combination of dry as well as frozen and fresh/live foods will ensure a well-balanced diet. Dry foods come as pellets, flakes, wafers and sticks. Formulations for herbivores, omnivores and carnivores are easily obtainable in your local fish/pet shops (LFS), as is fish specific food ie food for bettas, goldfish, cichlids, arowana. Most foods available range in size from tiny pellets for fish with small mouths, to large sticks for the bigger predatory fish like Oscars or Jaguar Cichlids. Each food type has its pros and cons – sinking wafers are great for catfish but no good for surface feeders ie Hatchet fish, Pantadon Butterfly Fish. Flakes can be crushed or crumbled for smaller fish like Guppies and Neon Tetras but will not sustain large bodied fish as they do not contain enough bulk. Likewise large pellets are too big for fish with tiny mouths such as Mosquito Rasbora, or narrow throats such as the Rainbowfish species. Some pellets will float for a while before slowly sinking, often making these the preferred food for a community tank. The majority of frozen or freeze dried foods are processed organisms like brine shrimp or bloodworms. Some people believe that freeze-drying food retains more vitamins than freezing but both result in some loss of nutrition. Most fish prefer frozen foods over freeze-dried but freeze-dried are more easily crumbled for smaller fish. Commonly available freeze-dried foods found in NZ are tubifex, bloodworms, daphnia and de-capsulated brine shrimp. Brine shrimp, bloodworms, daphnia and mysis shrimp are some of the frozen foods available from your LFS. Most fish enjoy live foods. Foods like microworms, whiteworms and blackworms are easily cultured at home. Daphnia can be found in water troughs and ponds exposed to the sun while mosquito lavae can easily be cultured by leaving a bucket of water, with a handful of grass added, out for the mosquitoes to lay their eggs in. Larger predators will also enjoy worms and crickets. More experienced fish keepers and breeders also hatch bbs (baby brine shrimp) for feeding to their newly hatched fry or grow-out tanks. Beginning fish keepers – the majority of new fish keepers tend to start off by purchasing fish such as guppies, neons, and the danio species (all small tropical fish), or mountain minnows (coldwater fish). Another fish, which is popular with new fish keepers is the dwarf gourami. Bristlenose catfish and corydora (cory) are also fish commonly purchased by new fishkeepers. You will note that there are blanched vegetables listed below for some fish – vege clips can be purchased from LFS, for around $11, to hold these and prevent them from floating around the tank. Guppies Flake food (crushed finely), micro granules, decapsulated brine shrimp, finely chopped frozen bloodworms, mosquito larvae Neon Tetra/ Cardinal Tetra Flake food (crushed finely), micro granules, decapsulated brine shrimp, finely chopped frozen bloodworms Zebra Danio/ Leopard Danio Flake food (crushed), decapsulated brine shrimp, finely chopped frozen bloodworms, microgranules, daphnia, blanched spinach, zucchini (courgette) Harlequin Rasbora Flake food (crushed), micro granules, daphnia, finely chopped frozen bloodworms, blanched spinach, zucchini (courgette), skinned peas Dwarf Gourami Flake food (crushed), micro granules, frozen bloodworms, mosquito larvae and daphnia. Bristlenose Catfish Blanched zucchini (courgette), carrot or broccoli, algae wafers, pellet or flake food high in vegetable content. Corydoras Shrimp pellets, algae/vege pellets, frozen blood worms Mountain Minnows Flake food (crushed finely), micro granules, daphnia, mosquito larvae, decapsulated brine shrimp Goldfish are a cold water fish which new fish keepers often purchase. The type of goldfish you buy largely determines what sort of food you should feed it, as does whether or not it is to be kept in a pond or a tank. I will just cover food for a goldfish in a tank. If you have a goldfish like a Comet or a Shubunkin, which are the original shaped goldfish, then a high quality flake or sinking pellet food will be good for them. Lower quality will cloud your tank water quickly. However if you purchase a fish like a Blackmoor, Oranda, or any fancy goldfish for that matter, you are better to feed them a sinking pellet food. The reason for this is that the swim bladder in fancy goldfish is packed in tightly and when they come up to eat flake foods it is common for them to suck in air while eating. The location of the swim bladder makes it very difficult for this air to be released. Comet Shubunkin Blackmoor Oranda “In terms of fish food, variety truly is the spice of life. Just keep it fresh and feed it lightly." ~Ted Dengler Coletti © This item may not be reproduced without written permission
  13. My Fish Just Died Adapted from an article written by Bill (PegasusNZ) So your fish just died, or are they dropping like flies. What do we do? If your fish has no visibile signs of injury then usually we tend to just accept it as one of those things that happens, but in many cases, and with little effort, a few things can be learned from the deceased fish. Unless your fish died from old age, which few fish do, then we need to establish if possible what caused its demise, but how do we approach this? Of course our first objective is to test our water, but if this shows no obvious causes then what do we do? External examination of the fish can reveal many things, and apart from the obvious wounds, which might have been inflicted, there are other things we can look at. Parasites are one of the main causes of fish deaths, and we get internal and external types that can sometimes lay dormant for months, then suddenly wreak havoc on our tanks. Bacteria buildups in our water can cause many problems, from inflamed gills to stress and breathing disorders. Fungi of various types will affect fish with open wounds, or fish in an unhealthy condition that have lost their immunity to resist the spores that linger in wait for the slightest chance to attack. Body slime, clouded eyes, fin and tail rot, and shimmies, are all visible external signs, as are spots, blisters or cysts of any type or colour, which can include white spot and a yellow looking spot that could be Velvet disease, or an ugly parasite that has burrowed under the skin of the fish. Then we have such things as Pop Eye caused by gas behind the eye, Dropsy, which shows protruding scales, and Swim Bladder problems, all which show visible external signs. Many of the above can be treated with various medications, but then we get the scenario where a fish refuses to eat, or lurks in a corner for days on end, or is just found dead in the tank one morning, or perhaps it was dashing madly around the tank before it died. Death by stress is hard to determine, as usually there are no visible signs. Observing, not looking, at your fish each time you have a chance will tell you many things, and by doing this you begin to understand each fish and their general habits. It makes little difference if you keep Goldfish or exotic species of marines that cost thousands, the same rules apply. They can't tell you they are ill, but they can show you in most cases, and anything that does not look should be treated with suspicion. Usually anything differing from these habits can be spotted soon and action taken. Flicking on objects in the tank is a sure sign of trouble, not feed, trailing faeces, cloudy eyes, patchy colours, slimy skin, cloudy skin, bloated body, erratic swimming, restless and lethargic behaviour are all signs you should be look for, as all mean that trouble is just around the corner. Dinner time should be a mass of activity for all fish in most cases, and that is a good time to do a number count if that is possible. All external parasites can be identified such as Anchor Worm, White Spot, Flukes, Fungi, and so on. With a good quality scope we can also see various bacteria, but know the good ones from the bad is still beyond me. Just finding simple answers can be so rewarding, even though you did lose a fish in the process. These are the mysteries, the unknown causes that lead to the deaths of our fish, which can in many cases be looked into in a different manner in the hope of finding at least some answers to these mysteries. Someone recently asked me about fish deaths, and I made the statement that if a fish of mine dies, and it is not through any fault of my own, then I want to know the reason why. In my early years, fish deaths caused me a great deal of concern, and more so when they became my means of earning a living. I learned in my early years how to dissect a fish and examine the various parts with both a strong hand glass and a microscope. For quite some time it was still all just a mixed up mess of internal organs that I was not too sure if they were healty of not, so I took some less and advice from a professor friend of mine at university and came away a little wiser, but still a little confused. It was not until I compared a previously healthy dead specimen to an infected one that i became aware of the various differences in the two dead fish. Guppies, Platties, Mollies and Swordtails were my test cases, and from these I learned a number of things. The Microscope This is such a handy piece of equipment if you want to delve into the inner workings of fish, for with it you can not only recofnise some of the major parasites, but you can examine algae, your water, plant structure, along with just everything that can attack your fish internally or externally. Algae alone holds a world of information, with unbelievable shapes and patterns that have to be seen to be believed, and your water, both drinking and in your tanks, hold more than you could possibly imagine. To me the microscope became in a sense much like being a diver. The non-diver can only look at the ocean from above, and sees a huge body of water holding untold mysteries, but seeing that same ocean from beneath the surface is a completely different world, one that never fails to fascinate me, and is different at every dive, even in the same area. MY many years of diving are gone, but the memories remain, and hopefully always will.The microscope is very much like this, for you are taken into a different world, one of which has been in existence since the beginning of time. By just taking smears from infected parts of fish you can begin to recognise the microscopic life that infects our fish. With observation you can spot a healthy organ from an infected one, and examine all parts from the mouth to the anal region, which will tell you many things as to why your fish died. The intestines, the alimentary canal and the stomach will tell you exactly if the fish was eating, and what it ate for its last meal, and will also tell you if that meal was recent, or some time ago. The intestine is short in flesh eating fish, and long in vegetable matter eating fish. Discoloured organs will give you clues also, and inspection of the swim bladder will in most cases enlighten you about swimming disorders. In Catfish the swim bladder differs to the normal fish. The world of wonder grows with each slide you make. You don't have to be a scientist to look at these things, nor do you need a microscope costing mega bucks to observe some of the above, as a simple microscope from a child's toy store will reveal many things. I have had several over the years, and now I am look at buying another as my last one mysteriously disappeared. One of my early ones was made entirely of brass, was very old indeed, and had a single lens, but the workmanship was outstanding and it gave me a lot of pleasure. Ones with built in lights are better than the reflector type, and three optics are always better than one. The quicker you examine the fish after death, the better your chances are of seeing the parasite or infection in its active state. Once you isolate the culprit take a slide and a slip and make up a sample that you can keep for future reference. I am no expert in this field, but I don't like to accept something happening that I know nothing about, so to this end I tried to learn all I could about the life and deaths of my fish. Make it your foal to learn something new about your fish every day, should it be from reading a book, or surfing the net and forums, but do it. The knowledge you gain will never be wasted, not if you keep fish. It is a well documented fact that a huge percentage of fish deaths are caused by their owners, either through neglect, or even over indulgence of kindness where we tend to overfeed, or add this and that to our water (just in case), or neglect to consider the 'soup' that our fish are swimming in. Perhaps if you had done that water change instead of just topping up with water your fish might be still alive, or perhaps you changed too much water, or it was too cold and caused great stress to your fish. These are things that only experience and time will tell us where we went wrong, but watching others and learning all you can from any means possible is the best advice you can get. We have all lost fish, and made many mistakes, but with the technology of today perhaps our chances of success have just been increased by a huge amount. Reaching that perfect balance where both your fish and yourself are without stress can sometimes be hard to achieve, but invariably if your fish are happy, so are you. © This item may not be reproduced without written permission
  14. Aquarium ConditionsAuthor: Warren Stilwell First published in Aquarium World November 2000 This article is based from experience and many of the insights contained in the book ‘The Optimum Aquarium’ by Kaspar Horst/Horst E. Kipper (ISBN3-925916-02-4). This book is a wealth of knowledge for anyone who strives for perfection. Unfortunately this article assumes a certain basic knowledge about water chemistry that might go beyond what some people are willing to research, but do read on anyway, it’s not all like that. One of the most pleasing looking aquariums is that which mimics nature as closely as possible. This can be quite challenging given the limited space and budgets imposed upon us. If we are to expect the best from our hobby and the best for our pets we must aim towards creating this goal. It is however not always practical to try to imitate nature exactly, as in many cases it would be highly unstable. Below details two ways of setting up an aquarium system that will cater for almost all types of fishes. There have been major advances in technology for aquarists over the past few years. Most of these advances are not mentioned in the many books that are available today to help us with our hobby, passion, or obsession. This is due to most of the literature being at least 10 years old, and written by people who have successfully kept fish for many years without this technology. Many of us have less than optimal conditions in our aquariums. This comes about for many reasons. Some of us are too busy. Others do not want the hassle of regular testing and lots of maintenance. In today’s society it seems there is always less and less time available for our hobbies. There is hope however. Much of the new technology available today helps reduce maintenance, and can extend the time between water changes. Alternatively, it can improve water quality in an existing system. These, of course, do come as a financial trade-off, but what doesn’t anymore? All this said however, there is no substitute for regular care of our pets. The Goal:We all want a clean looking aquarium with no or little algae, lots of colourful fish, and no need for water changes. Well, unfortunately this cannot be achieved easily, and water changes will always be required. In nature the ratio of water to fish is millions times what we have in our aquariums. Even if there are 100 fish in a 1m2 area, this is compensated for by 1000 litres per second water change or 100,000 litres of water around them where there are no other fish. These 100 fish in our aquarium must however cope with only 250 litres of water which is recirculated (not changed) maybe 2-5 times per hour. Waste products and unwanted nutrients build up very quickly in a small closed system like this. Typically in smaller tanks the problem is worse, while in larger tanks it is better. Water Chemistry:In nature the water is relatively low in algae producing nutrients. In many areas the water is very soft (1dH or less) with the exception of Africans and a few other specific species. If these conditions were replicated in the aquarium, many things would start to go wrong immediately. Because there are virtually no nutrients in very soft water the PH can change very quickly as the fish waste product builds up. In nature there is stability only because of the massive amount of water volume or water flow. Example:Set up a 100 litre tank and fill with distilled water. Add sodium bicarbonate (Baking Soda) to get a carbonate hardness of 1dH. Add sulphuric acid to adjust the pH to 7.0. 100 litres is quite a lot of water, but you would be surprised to find that is only takes ½ a teaspoon of baking soda to get 1dH carbonate hardness. It also only takes a few drops of acid to bring the pH down to 7.0. If this tank is left covered and sealed in the sun for several weeks, virtually no algae form, and the pH will remain relatively stable. If this tank is then uncovered, gases will dissolve into the water and change the pH. Only a small amount of gas can dissolve however, so the resulting change in pH can be compensated for with either acid, if pH goes up, or baking soda, if pH goes down. After many weeks, a small amount of algae may start to form in the tank. This is due to dirt and dust falling into the now uncovered water. This dissolves and starts to build up a nutrient load. Algae spores also float in the air and land in the tank. Now that there are suitable nutrients and algae spores, algae will start to grow. The quantity of algae however is very small. We now introduce one very small fish, a neon for argument sake. This neon must be fed, which will leave uneaten food to pollute the water. The neon also releases waste products into the water. After 1 day of feeding and waste production from the one tiny fish, there are more nutrients in the water than in weeks of having no fish and the aquarium. Within days algae start to form in significant numbers, and by the end of 2 weeks the glass is covered with thick algae, and the water is green. Also massive pH shifts have occurred that, left unchecked, will kill the fish. All this has happened with only the faintest trace of pollutants in the water. This highlights the problem of keeping fish in a closed system, and indicates the need for some way to clean the water. Setup Types:There are only 3 ways to set up an aquarium so that it is low maintenance and relatively algae free. The first is the easiest, and long term is the cheapest. This is the heavily planted tank with a small fish load. The second is for aquariums that cannot be a plant tank – large cichlids, plant eaters, or African cichlids. The third is to condition the water coming into a tank to the correct pH, hardness and temperature before it enters the tank, and have a continuous water change system that changes the water 1-5 times a day. The third method is often not practical and being self explanatory will not be detailed. Many of the requirements mentioned below are required for both types of aquarium, but type 2 is mentioned first. Setup type 2: Large Cichlids, Plant Eaters, and Africans. Large cichlids continuously disturb the substrate, digging nests, or just digging for fun. Plant eaters are often so voracious that no matter how many plants, and how few fish you have, the plants always lose. Also, this type of fish often seems to delight in biting the plant off near the roots so you find the top 90% floating at the surface. The plant is often then useless, as it will not re-root before dying. African cichlids require water conditions that do not suit plant growth as the water is too hard. There are some plants which will survive but will not grow fast, or well enough, to out-compete the algae. There are of course exceptions to these rules where someone has got lucky with their setup, but that is what it is, luck. This type of setup is often not repeatable on a large scale without significant problems occurring. The only way to be successfully algae free in a plant free tank is by fine mechanical filtration, massive biological filtration, chemical filtration and regular water changes. The water changes must be quite large (at least 50%), and done often (once a week minimum). Massive water flow through the filtration is required also, at least 5 times the tank turnover per hour. The filter must also be large. Basic Setup:It is possible to use an undergravel filter and coarse gravel (4-10mm) for this setup. The only problem which may occur with some species is that they might dig right down to the undergravel plates, rendering this filter almost useless. An external power (trickle is best) is required to get good water conditions. It is only necessary to create a natural looking habitat for the species you wish to keep. Mechanical Filtration:The best success can be achieved using a pleated cartridge filter of 10 to 15 microns. The most common type is used on Spa Pools to remove debris from the water. The purpose of this filter is to remove all small non-dissolved organic matter from the water. This filter is changed every few days. This stops the organic matter from decomposing in the tank or filter system and increasing the nutrient load. Biological Filtration:A large surface area of biological filter is required. This is best in the form of a trickle filter. There are many different types of media available for biological filtration, but the best is usually synthetic media with extremely large surface area (450m2 to 1350m2 per litre of media). This will ensure that all dissolved nitrogen compounds are quickly turned into nitrates. As long as nitrates are low (less than 20ppm) algae will be minimal. In some of the newer synthetic media, anaerobic areas will form that will also help to lower the nitrate level. Water changes are still required, however, to keep nitrates under control. There will be more to come in a special article about filters in the next Aquarium World. Chemical filtration:This is paramount to stop algae forming, and keeping the water clear, sparkling, and to keep unwanted nutrients to a level below the alga threshold. Carbon is good for removed the aged yellow look of the aquarium water, but does little else to stop algae. It does not remove significant phosphate from the water. All organisms require phosphate to survive. It is one of the major building blocks of life. The problem is that you add phosphate to the aquarium regularly in the food. Phosphate absorbing resins are the best solution to lowering the level to that required. Water changes:Water changes are 100% essential. The time between water changes is much too long in many cases. The regularity will largely depend on the size of the filter, number of fish and the size of the tank. It may be possible to skip changing the water in an aquarium for 3 months, but just think how you would feel wearing the same clothes for the same time. Most of the successful breeders in the world do daily or even twice daily water changes of up to 90%. Your fish will appreciate the maximum amount of water change you can possibly do. This does not mean changing 90% every day, but it is amazing what 10% a day can produce. However, many tap water supplies around the country are rich in phosphate, and many brands of activated carbon release a small level of phosphate into the water when first installed in the filter. A 100% phosphate free water source must be used for water changes otherwise the algae are just being fueled. A target level for phosphate in aquarium is below 0.1ppm. If you have a 1000 litre barrel of distilled water, this equates to 0.1 grams of phosphate (about enough calcium phosphate powder to cover your small fingernail). This is a very small amount. Of course, if you are breeding fish in an all glass tank, and can regularly wipe the algae off the glass this is not a problem. It is often not practical to try to remove the phosphate from the water if the amount required is large. Setup Type 1: Planted Aquariums. The planted tank can house a very wide variety of the commonly kept and possibly more popular smaller fish. Many of these fish prefer heavily planted tanks as it is closer to their natural habitat. The setup of a planted Aquarium is very similar to the previously mentioned system. There are some major differences however. The plants in a heavily planted aquarium work as a filter. They use nitrogen waste product from the fish and uneaten food. If the correct ratio of fish to plant is used it is possible to omit certain filter items. Planted tanks require quite soft water, and a pH of 6.5 – 7.0. A good compromise is 6.8. This suits most of the fish that would be kept in this type of aquarium, and is also best for the plants. The most important part of this type of aquarium is the plants, the fish are secondary. Basic Setup:Undergravel filters cannot be used for this setup. Gravel of 2-4mm is best as a substrate. Iron containing additives can be added to the lower layer of the substrate, but it is not essential if regular substrate fertiliser is used. Undergravel heating is also very beneficial. When planting out the aquarium, at least 80% of the aquarium must be covered initially, and no fish added until the plants have settled in (4-6 weeks). Mechanical Filtration:The same mechanical filtration is required, however it can be quite a lot smaller. This is due to a lower waste product load on the system. Much of the collected organic matter will be from dead plants, where it would be uneaten food, and fish waste in the other system. The same requirement for changing the filter exists (4-7 days). The more often this filter is cleaned / changed, the cleaner the aquarium is, and less bio-load there is on other parts of the filter. Biological Filtration:This is also the same. There will be less nitrogen compounds for the filter to process due to the plants however. The filter is a safety mechanism an also helps to provide water circulation. Chemical filtration:This is often not required any more, or maybe occasionally to just take a slight yellowing off the water. The plants are so effective at cleaning up that this type of filtration is seldom needed. If all is set up correctly and relatively balanced, the plants will utilise all the available free phosphate. Fertilisers:Planted aquariums need regular fertilisers. The type of fertiliser will depend on the conditions, fish load, lighting, CO2 and water changes. The nutrients contained in the fertiliser are extremely important as they must benefit the plants, but not promote algae. A good water fertiliser should not contain any phosphate and be rich in iron. A good substrate fertiliser should be rich in iron, and contain some nitrogen and phosphate. In both there should be trace elements in the correct quantities. The objective is to sustain a balance of the correct nutrients, with no one nutrient becoming dominant. This is achieved by regular water changes and the daily addition of fertiliser. The contents of the fertiliser are unfortunately beyond the scope of this article as it would be equally as long is this one. Water changes:Water changes are still required. In this type of system, it is more vital that water changes are done. The previous system will forgive to a greater or lesser degree a missed water change. A planted aquarium will quickly begin to show you when you need to do a change. It is of course better to do a change well before this, as it takes a while to recover from such an event. Regular water changes keep a more constant balance. Other than water, the less you change (pH, hardness (dH and kH), nutrient levels etc) the better of all your aquarium inhabitants will be. Water Chemistry 2:As previously mentioned, it is not practical to try to keep natural conditions in an aquarium. Only when a carbonate hardness of 4dH or greater is sustained will the pH be stable. In an African tank the dH will be much higher anyway. The target is to research the required water chemistry for the species you wish to keep and as best as possible create it with the above exceptions. Happy Fish:If the natural conditions for the species are created, they will be more active, spawn more readily, and grow faster and stronger. To achieve best results a limited number of complementary species should be grouped together, with the ultimate system containing only one species. On the whole, if breeding a specific fish is the target then a single species tank is essential (sometimes 1 or 2 fish of another specific species will be required to initiate spawning). Fish that compliment each other are those that are found I nature living together. It is not practical or wise to put a Neon and an African together for example. Apart from the Neon requiring soft low pH water and the African requiring Hard high pH water, the African will probably also eat the Neon. In many cases incompatible fish are mixed together and while they might survive, they are not at their best. Costs:Setup Type 1 costs a little more to get going because of the large outlay for plants. The long term running costs are much lower however, – fertiliser (that you can make yourself) and mechanical filter cleaning products are the only on going costs. Setup Type 2 is a little less expensive to get going, but has relatively high running costs. The quantities of activated carbon and phosphate resins are quite large. They are also not cheap. The same cost for mechanical filter cleaning product exist. Ways to get Good Water:Good water, – what is it. As previously mentioned, good water has no phosphate, no nitrate, nitrite, or ammonia, and has the correct PH and hardness for the species of fish(es) you keep. To obtain this there are several methods. If your tap water is suitable, use it you are very lucky. It pays however to monitor the quality of your water as it can change from winter to summer as the demand for water changes. Water fed from wells often changes quality depending on the quantity of water drawn from it and what it passes through on the way to your tap. If your water is unsuitable there are several alternatives: Rain water. This is often quite good, but can be too soft for Africans and many harder water species. Care needs to be taken here because pollutants like heavy metals and hydrocarbons can sometimes appear in the rainwater. These are toxic to your fish. Processed tap water. If you can store water in a separate tank and process it with phosphate and ammonia removing resins it is possible to get suitable water. This can also be pre heated to make water changes easier. Reverse Osmosis. RO water is by far the best, but is far too pure to use on its own. It also needs to be stored separately from the tank so it can be conditioned before being used. Salts and trace elements must be added before RO water is suitable. This stabilises the pH also. It too can be preheated. De-Ionised water is as good as RO water, but is often very expensive to produce. It requires the same conditioning as RO water. The above methods (especially RO) may need extra salts and trace elements added to the water before it is suitable for the species of fish it is intended for. The requirements for these salt and trace elements are also beyond the scope of this article, but will be detailed in an article in the next Aquarium World. Summary:The overall aim is to make our fish as happy as possible. This is a challenge that gives us pride in our hobby once we achieve it. There is nothing better than sitting down in front of a good display aquarium to enjoy its beauty and see the occupants behaving as if or almost as if they were in the wild. This is more so when it is your own aquarium. Most of the information you need to set up the correct conditions is in books, and quite often on the internet. Good Books:The Optimum Aquarium (Kaspar Horst / Horst E Kipper) ISBN 3-925916-02-4 This is an excellent reference book that covers planted aquaria. The Biotope Aquarium (Rainer Stawikowski) ISBN 0-86622-519-6 This is an excellent all round book that details the basic habitats of nearly all type of fish. The Natural Aquarium (Satoshi Yoshino and Doshin Kobayashi) ISBN 0-86622-629-X A different book but similar to the Biotope Aquarium. Nature Aquarium World 1,2 and 3 (Takashi Amano) ISBN 0-7938-0089-7 There are three books in this series. There is limited information in them, but it is all good. The emphasis is totally toward the planted aquarium. The photographs are nothing short of incredible. The series gives you examples of many different themes for a planted tank, and once read you will not be able to settle for just one aquarium, you will have to have lots. © This item may not be reproduced without written permission
  15. Marine starter guideAuthor: Wasp First published in Aquarium World November 2007 A marine tank is a fascinating hobby which gives the owner not only the chance to keep some very colourful fish, but also the chance to grow living corals, have invertebrates such as crabs and shrimps, and if skillful enough, come close to recreating a little piece of coral reef ecosystem. Even some of the amazing symbiotic relationships that happen between various species can be done in a reef tank, such as the clownfish and anemone combo. Anemones with clownfish living in them can be kept in a reef aquarium. This is a beginners’ guide, the idea being to give a prospective reef tank keeper (reefer), an understanding of the basics. However there is much more to learn than this article, so then you are invited to start a thread in the FNZAS website forums with any more advanced questions, and questions specific to your own tank you are setting up. This guide is divided into several sections with a basic explanation of each. Sections:- Cost Water quality and filtration Phosphate Water chemistry & chemical additives Sand Light Water movement Fish Corals Putting it all together; How to construct a basic 1.2m (4ft) reef tank CostThis is going first because it is important to realize that setting up a reef tank properly is not cheap. To do a basic reef tank but do it right, you are looking at a minimum of $2,000 and upwards from there. In fact there are many reefers who have spent 10, 15, or $20,000 on their hobby. Here the confusion sets in because you will sometimes hear people claim they set up their tank for “500 bucks”. While this may in some cases be true, it will be because the person got some second hand equipment at a good price, or they set up the tank and it is in fact running, but down the track there will be problems because of el cheapo equipment. There is also the occasional person who breaks every rule and gets away with it. However over the years I have been saddened to see so many keen people start up, put so much time and love into their tank, but eventually fail because they could just not afford to buy the right equipment. It is important to understand up front what finance must be committed, rather than go through all the heartbreak of running something that is just not going to work, having livestock die, and eventually leaving the hobby disillusioned. Water Quality and FiltrationCoral reefs in the wild grow where water is clear, clean, and pristine. In our tank we have to keep water to very high standards of cleanliness. Do this and success is virtually guaranteed. Don’t do it and failure is virtually guaranteed. PROTEIN SKIMMER; Nearly all reef tanks use a protein skimmer. A protein skimmer removes small particles of dirt, bacteria, and whatever, from the water. The way it works is by pumping the tank water slowly through a vertical tube which has fine bubbles injected into it, either from an airstone, or of recent times, by more advanced and effective means such as air injected needlewheel pumps. The bubbles form froth at the top of the tube, and this froth collects dirt that has attached itself to the surface tension of the bubbles and risen to the top. As the froth builds up it overflows into a collection cup along with all the impurities it contains, and in this way a good quality skimmer will remove a high proportion of undesirable pollution from the tank. LIVE ROCK; Virtually all reef tanks use live rock to facilitate bacterial reduction of the waste products that the skimmer didn’t get. Live rock is harvested from areas around coral reefs, and is made from old coral skeletons that have formed into chunks of rock. It is light and quite porous which provides an ideal living space for bacteria that eat waste products floating around in the water, and break it down to less harmful products. NITROGEN CYCLE; This is a short explanation on how the bacteria in the live rock actually break down the waste. We add fish food to the tank, and all the various living organisms in the tank excrete waste, which if not removed would rapidly build up and kill everything. Nearly all organic waste becomes ammonia, which is highly toxic. However mature live rock contains bacteria that specialize in eating ammonia, and they turn it into nitrite. Then nitrite eating bacteria turn the nitrite into nitrate. Finally nitrate eating bacteria eat the nitrate and turn it into nitrogen gas, which leaves the tank through normal gas exchange at the surface of the water. In NZ, live rock is often purchased dry, and the bacteria are dead, or have formed spores. This live rock has to be “cured” which means left in water for a period of 6 weeks or longer, until all the various types of bacteria have established themselves and the rock can be used to provide filtration in a tank. These are the two main essentials for good water filtration. Live rock, and a good quality protein skimmer. However here is a brief explanation of other things that can be used at the owners discretion. Carbon is used to purify water, it can be purchased at a local pet shop (LFS) and is put in an area of high water movement. As water passes by it, waste gets absorbed into the pores in the carbon. Other filtration media; There are other filtration media available from the LFS, that are used in the same way as carbon, but are designed to target something particular we want to get rid of, such as phosphate. UV units are essentially a tube with a powerful UV light bulb inside. Tank water is pumped through the tube and the UV light breaks down complex organic waste into other forms that are more easily removed by the protein skimmer, or used by bacteria. Canisters, hang on filters, trickle filters, and other highly aerated filtration types used in fresh water tanks, should NOT BE USED in marine tanks for biological filtration, although they can be used to hold carbon or similar. The reason is that nitrate reducing bacteria cannot function in a highly aerated environment, and use of these filters will result in a build up of nitrate to levels that are harmful to many reef dwelling creatures. In a marine tank use live rock to house the bacteria. Deep within the pores of the rock, where there is less oxygen, the nitrate eating bacteria can do their job and keep nitrate levels low. PhosphatePhosphate really comes under the filtration section but because a good understanding of the topic is often critical to success or failure it is listed in its own section. Phosphate is an essential component of living matter, and all living matter contains it. However in a reef tank it can often be the enemy as it can accumulate to unnaturally high levels and cause problems. Phosphate is in fish food, and every time fish food is added to the tank, some phosphate goes in. One way or another fish food eventually becomes waste and is removed from the tank by the nitrogen cycle. Phosphate though is not part of the nitrogen cycle and is left behind in the tank, slowly becoming more and more concentrated. Too much phosphate causes two main problems. One is that it precipitates onto calcium carbonate, which is what corals build their skeletons from. In this way it can slow, or even completely prevent, coral growth. The other problem is that phosphate is used by algae. If there is too much phosphate in a tank, this will act as fertiliser to algae, and the tank will turn green. On the other hand, even a green, algae ridden tank can be fixed, by removing the phosphate, and the algae will die. So a very good part of filtration and water quality, is actually about phosphate control. There must be a means of “exporting” phosphate from the tank at least as fast as it is being added. One of these ways is the protein skimmer. The organic waste that the skimmer removes, will have a phosphate component. In a lightly stocked tank with a good quality skimmer, just the skimmer alone may be enough to keep phosphate at acceptable levels. In addition to this, regular vacuuming of the tank removes much waste that would eventually release phosphate if left. Also the amount of food being put into the tank should be looked at. Fish in the wild usually do not know where their next meal will come from, so given the opportunity will gorge themselves with all they can. This makes it tempting for the aquarium keeper to throw much more food in than they actually need. Often a new reefer will be surprised to discover they can cut the amount they are feeding in half with no detrimental effect on the fish at all. This will of course cut phosphate levels in half right there. However, often more measures to control phosphate are required. If phosphate is accumulating despite the skimmer and your best efforts at vacuuming, a phosphate absorbing media can be used. This is a resin of smallish particles that can be put in a bag and run in a canister or similar, or in a specialist phosphate reactor. In a green tank the effect of running phosphate removing resin can be dramatic, with algae turning white and dying within a few days. Or in bad cases it may take several weeks or months to get phosphate down to excellent levels where algae cannot survive. The presence of too much phosphate is often best judged by algae growing and/or less than clear water. Test kits can be less reliable. This is because some of the phosphate in a tank will be precipitated onto the substrate, some will already be within living organisms and algae if there is any, and only a tiny percentage might be in the water. So testing the water with a kit, will not indicate the total amount of phosphate in the tank, only the smallish percentage of it that is loose in the water. Phosphate tends to be taken out of the water by precipitation and grabbed by life forms, and only is in the water in large amounts if things are getting really bad. So a test kit may indicate you have no phosphate, when in reality the tank contains way too much. In general, if your test kit tells you there is any phosphate at all, you have too much. Water Chemistry and Chemical AdditivesHuge volumes can be written on water chemistry, so the following is basic information only, not an exhaustive study. There is much more, but this is what you HAVE to know. The chemical parameters of most interest to reefers are salinity (salt concentration), which should be approximately 1.025. Then there is calcium around 400 mg/l, alkalinity around 7 – 11 dkh, and magnesium around 1250mg/l. PH also should ideally be around 8.3 although anything 8.0 – 8.5 is considered OK. Salinity tends to slowly increase as water evaporates and concentrates the salt, so more fresh water has to be added to keep it at the right concentration of 1.025. Slightly higher or lower than this can be used. RODI filters (a very high standard water purifier) should be used to treat the fresh water you add to the tank. Calcium and alkalinity are slowly removed from the water as corals use these to build their hard skeletons, and this has to be replaced. The three main methods to do this are firstly kalkawasser (lime water), which can be slowly dripped into the tank, or secondly 2 part additive which is a calcium mix, and an alkalinity mix, which are added separately but have to be in balance with each other. The third way is a calcium reactor, which is a tube that holds calcium carbonate rocks. Tank water is slowly pumped through, and carbon dioxide gas is injected which slowly dissolves the calcium carbonate into the water, thereby raising calcium and alkalinity levels in the tank. People wishing to use any of these methods can do further research on our FNZAS forum, and Google. pH in a reef tank, is determined primarily by the amount of CO2 in the water, and the alkalinity. Provided the alkalinity (dkh) is at the correct level and there is sufficient aeration, pH will be at the right level. Magnesium is needed at a level at least 3 times that of calcium, because without it the calcium quickly precipitates out of the water. So to maintain a calcium level at 400mg/l, you would want to keep magnesium at least at 3 times that, or at least 1200mg/l. There are many other chemical parameters, and a host of additives for sale to dose them. However for the beginner, just keep salinity, calcium, alkalinity, and magnesium at the right levels, and you will do well. Beware the large amount of other additives for sale, it is very tempting to buy all sorts of expensive stuff to dose into our tank, but the benefit of a lot of them is questionable, regardless of how important the label may tell you it is. If tempted, ask on our forum. SandSands based on calcium carbonate tend to be the best for a reef aquarium in terms of the effect on water chemistry. These are sold in New Zealand as aragonite and calcite. As to grade, too small and it clogs and is hard to vacuum, and too big and food etc can easily disappear into it before the fish even eat it. A happy medium is a grain size around 2mm or so. How much sand, and whether to have any at all, is a subject of much discussion in reefing circles. There are three main options. A deep sand bed (DSB), a shallow sand bed (SSB), or a bare tank bottom with no sand (BB). DSB is defined as a sand bed at least 10cm thick. At this depth the bottom of it will be anaerobic (not much oxygen), which enables nitrate eating bacteria to operate, so a DSB can be an effective way to reduce nitrate levels in a tank. The other thing a DSB does is absorb a lot of muck and also phosphate from the rest of the tank. In the short term, this can be a good thing. But longer term the DSB can get so full it can become a source of pollution to the tank and cause the tank to “crash” (wipeout). SSB is defined as 5cm deep or less. At this depth it will have little or no nitrate reducing properties, but on the other hand, is much easier to vacuum and keep clean. BB is used by people wanting high water quality. With no sand at all, any dirt on the bottom is easily seen and available to be siphoned out of the tank. LightLight is important because many of the organisms in a reef tank use photosynthesis, and without the correct amount and type of light, they will die. Lighting is provided usually by either fluorescent tubes or metal halide lights. As a rough guide, allow 1 watt of light per litre of tank water as a minimum. Some corals are happy with this level of light, and others need more. Light “colour” is measured in Kelvin (k). Bulbs of 10,000k give off the most proportion of light that is useable to the corals for photosynthesis. However 10,000k can appear a bit yellow and a tank with a more blue light makes the tank more attractive to look at. Therefore many people will add some bulbs higher up the spectrum at 20,000k, which contains a lot more blue (actinic) light. Or some people compromise and use bulbs at 14,000k, which can be OK for the corals and look attractive. Water MovementThe ocean has a lot of water movement and corals are adapted to that and need it for cleansing themselves and other purposes. In our aquarium we have to imitate this, and put pumps in to move water around if we want our corals to do well. Basic rule of thumb is to have a minimum of 10 x’s water flow i.e., the volume of the tank should be pumped 10 times an hour. So for example, if a tank is 200 litres, we would want pumps equalling an output 10 times that, or 2000 litres per hour. 10 x’s flow is a minimum, some corals like a lot more than that, some aquaria use 50 x’s flow, and even 100 x’s flow is not unheard of. To facilitate this there are special pumps available that clip to the side of the tank and pump large throughputs of water, specifically designed to produce large flow at zero head pressure. Some of them come with electronic control gear that can vary the flow to simulate wave action. Water flow should not be blasting a coral from one direction only, ideally the flow should be chaotic, going one way, then the other. This is best achieved by placing a number of pumps around, pointing various directions and even at each other, so that the water is swirling and surging in the tank, corals love to be washed one way and another, and will respond well if water flow is set up correctly. The other important function of water movement in a reef tank is to swirl the water around the live rock thereby enhancing bacterial filtration. The tank should have no dead spots, and the better the circulation is the better the water quality will tend to be. FishPrior to purchase research should be done on each species of fish. Some will not get on with others and some need certain environments that your tank may not meet. The great majority of fish for sale are wild caught and can come with a number of diseases. The use of a quarantine tank is a good idea, the fish can be kept in it for a few weeks to ensure it is not harbouring anything that could harm the rest of the fish in the tank. New fish sometimes have not yet learned to eat the kind of food we give them so a little research before purchase can help with useful information how to get the particular species settled in our system. Some fish are easy, and some don’t take to tank life easily. CoralsThis is what reefing is all about. The reef tank is really an underwater garden in which corals grow. They can be very beautiful and a well done reef tank can get gasps of amazement from anyone entering the room who has not seen it before. There are hard and soft corals, the hard ones are the ones that build a hard skeleton, and the soft corals do not have a hard skeleton. The soft corals are generally more easy care, and a few of them can stand considerable abuse in terms of poor water quality. The hard corals are divided into two broad categories, small polyp stoneys (sps), and large polyp stoneys (lps). SPS are the branching type corals people normally think of when thinking of a coral. Their polyps are small, match head size or less. They can be very beautiful, but are the most demanding of good water conditions, correct lighting, etc. Growing healthy sps corals is often regarded as the pinnacle of achievement for a reefer. LPS corals are demanding, but less so than sps corals. They like lower light and lower flow than sps, and some of them have brilliant colours. Their polyps are often around the size of the old 5 cent piece, but a few of them are much bigger. For corals to do well a high standard of water quality is required, more so than is needed for fish. Observation of the corals, and making sure that their water quality needs are met, is the primary concern and as long as that is done the fish will be fine. Nearly all corals for sale in New Zealand use photosynthesis. They do not photosynthesize themselves, but they have a symbiotic relationship with single celled algae type organisms called zooxanthellae, that live within the tissue of the coral, just under the surface. The zooxanthellae do the photosynthesis, and release the by products which supply the coral with nourishment. That, plus nutrients the coral absorbs from the water, can meet the feeding requirements of the great majority of corals. Some will do even better if we feed them directly but in most cases it is not essential. Feeding corals is a complex subject and it is best for the new reefer not to do this until gaining a reasonable understanding of the issues involved, or under the guidance of an experienced reefer. Putting It All Together. How to Construct a Basic 4 Foot Reef TankThere are many techniques and methods used to run a reef tank, and in advanced circles there is much debate over the finer points of which is best. However in the end they all boil down to a focus on keeping water pristine clean, and how to meet flow and lighting requirements of corals. The following is not the only way to build a reef tank, it is being offered as a guide to one way of building a successful tank. Our tank will be around 270 litres, and will be on a stand. The stand will have inside it another tank, 2 1/2 feet long (75 cm). This smaller tank will be the sump. The reason for this is that marine tanks require some bulky, and perhaps, ugly equipment, such as for example a protein skimmer. In order to avoid cluttering up the main tank with this, a smaller tank, known as a sump, is often set up underneath, or near, the main tank, out of view. The main tank has one or more holes drilled in the glass, and an overflow is built, down which water flows from the main tank into the sump. The sump has a return pump, which pumps the water back into the tank. Ideally the pump will pump the volume of water in the main tank approximately 5 times per hour. The sump can incorporate all equipment including skimmer, calcium reactor, heater, chiller, top up and dosing set up, plus a bunch of others. The water flows from the main tank to the sump for filtration and other treatment, and is returned to the main tank, about 5 times per hour. So now we have a tank on a stand, with a sump, and water circulating between the two. For water, we can either use artificial salt mix purchased from the lfs (local fish shop), that we mix with RODI filtered fresh water, or if we don’t want to buy salt mix we can use seawater collected when conditions are good and the water is clean. Seawater in New Zealand has a salinity around 1.028. The ideal for our tank is 1.025, so if using seawater we dilute it by around 10% with RODI water. We now purchase a high quality needlewheel skimmer and put it in the sump. Also we put a heater in the sump, set to 25 degrees. Into the main tank we place some pumps to make water flow. We have decided to go for 20 x’s flow, so for our 270 litre tank, we put pumps in with a total output of 5,400 litres per hour. Water is now swirling around nicely. Now we are ready to put some rocks in the tank. We do not put any sand in yet. One kg of rock to each 10 litres of water is about the right amount, our tank is 270 litres, so we purchase from our lfs 27 kg of dried live rock. This live rock is currently not live, so we have to “cure” it. To do this we place it in the tank. The pores in the rock are full of dead organic matter and in a few days starts to rot. The water goes murky and when we test the water with our test kit, we discover ammonia. Our skimmer starts working overtime and we continually have to empty it. Gradually ammonia eating bacteria get established, and in around 2 weeks ammonia drops to zero. Now with our test kit we discover nitrite, which is what the ammonia eating bacteria make. We also find a lot of sandy looking dirt on the bottom of the tank. This is waste coming out of the rock, and should be siphoned. This is why we didn’t put sand in yet. In about another 4 weeks nitrite eating bacteria are getting established and nitrite levels start to drop. We now discover with our test kit that the water contains increasing amounts of nitrate, because the nitrite eating bacteria make nitrate. During all this time we do not use the lights so that algae cannot grow. When nitrite levels have dropped to zero, we can start slowly adding livestock to the tank. But first, the water is now rather polluted. We drain all the water and replace with nice new clean water. Wait a few days and test for ammonia and nitrite just to make sure both are still zero, and if so, we are ready to stock livestock. We still do not add any sand yet. So, ammonia and nitrite must be zero. Nitrate is less toxic and does not have to be zero. The nitrate eating bacteria take several months to kick in, so rather than wait, we start stocking. Before adding livestock, we need some light. Nicely balanced lighting for a 4 foot tank can be done by 2 250 watt metal halides. This is giving 500 watts of light, nearly 2 watts per litre. It is enough that we can put high light needing corals on top of rocks near the lights, but it is not too much, so it will not burn lower light needing corals, which we put at the bottom of the tank. We use 14,000k bulbs, which gives a light pleasing to us the viewers, but still enough light that the corals need for photosynthesis. Once this is ready, we can stock fish and corals. There are two sources of corals, the lfs, or from other reefers who may be prepared to give you prunings (known as frags) from their corals. Because different corals have different requirements for light and flow, and can live or die depending on being placed correctly in the tank, be sure to research each one properly and place it not just where it looks good, but where it will do well. If getting them from another reefer take the opportunity to find out what’s best for the coral from them. For fish, we must stock slowly, over several weeks at least. The bacteria in the live rock have only just got established, and we do not want to overload them and risk another ammonia spike, which could kill everything. Some fish are territorial, and if you add them first, will claim the tank as “theirs”, and attack any fish you add later. To avoid this decide what fish you want first. Start adding the non aggressive ones and let them get established. Add the more aggressive ones last. Now we have corals, we need to start making sure water chemistry is correct for them. If we have any “stoney” corals (corals that build a hard skeleton) we need to ensure calcium, alkalinity, and magnesium are correct. So we purchase some calcium chloride, some baking soda, and some magnesium chloride. These are mixed with water and dosed manually into the sump as required. A more detailed discussion of additives is beyond the scope of this article, however information is available elsewhere on the site about this. In time, most of us tire of dosing manually, and move either to a mechanized dosing system, or a calcium reactor. In a few months we have a tank with corals and fish in it. There is still sandy type dirt appearing on the bottom of the tank from the rocks. We continue to siphon this out of the tank as needed, plus we do a 25% water change once a month. In time, the dirt shedding out of the rocks slows down, and we may now add sand if we wish. About this time algae will often start growing. It is important NOT to overstock the tank with fish. The more fish, the more we have to feed, the more phosphate, the more algae. We install a phosphate reactor in the sump. This deals to our algae problem plus has a beneficial effect on the tank in general. In time, the tank matures and stabilizes, and we find we can reduce, or stop altogether, use of the phosphate reactor. But if any algae starts to appear, we can turn it on. Basic test kits needed are ammonia, nitrite, and nitrate. Also Calcium, alkalinity, and magnesium. Get salt water ones, not fresh water. The other thing that is pretty much essential is an RODI water filter. This filters fresh water to a very high standard. In a marine tank we have to replace quite a bit of evaporation with fresh water. If we use tap water, or even filtered tap water, it contains phosphate. This phosphate will become more and more concentrated in the tank. The best way to avoid this is to use RODI filtered water. Many people fail to realize this and I have seen people leave the hobby because of the disappointment caused by problems caused to their tank by using non RODI water. The above is ONE way to build a successful tank, but it is certainly not the ONLY way. There will be experienced reefers who do things differently to the above method. However the purpose of this how to build a tank section is to provide information that will enable someone following it, to build a reef tank that will be a success. In ClosingThis article is in no way all the information that exists. It touches each subject only briefly, but at least you now know what the subjects are, and an idea of where to go from here. More information on all these topics is available on this site, and on Google. The best way of all if you definitely want to start a reef tank, is to contact someone who has one & see if they would let you have a look at it. Looking at the real thing while asking the owner questions can teach you much more in a shorter time. © This item may not be reproduced without written permission
  16. Stocking an Aquarium Author: Adrienne Dodge There is always a lot of discussion about how to work out the number of fish you can keep in an aquarium however this is dependent on many factors, ie filtration, plants, species of fish. Overstocking leads to stress, which can cause ill health among your fish and this in turn will reduce the enjoyment you will get from keeping them. If you get things right from the beginning you will have less problems with your fish and enjoy your tank much more. Aim to keep your fish in as natural an environment as you can. The two most commonly used guides for stocking a tank are - · The number of fish per litre of tank water · The number of fish per square centimeter (cm2) of water surface The second of these two, the number of fish per square centimetre of surface area is the better option as the surface area of the tank is where gas exchange occurs. The basic guide for tropical fish is 772cm of water surface per 2.2cm of fish SL1. For example a standard 60cm wide by 30cm deep tank has 18002cm of surface area. The basic guide for coldwater fish is 1542cm of water surface per 2.2cm fish SL. This guide is dependent on the fish in the tank being less than 6.6cm (SL) in length. Coldwater fish require lower stocking as the biological filtration works more slowly in cold water. The basic guide for larger fish is that the minimum aquarium should be twice the fish’s length wide and four times the fish’s length long. It is important when calculating stocking levels that you use the adult size of the fish in your calculations, not the size of the fish when purchased. It is also important you research first. Another important point is the known behavior of the fish you wish to keep, their varying sizes (big fish are known to eat any smaller fish that fit in their mouths), activity level, personality (do they like to be kept in a group or are they loner fish) and their preferred habitat. Tropical and coldwater fish will not be happy together, African cichlids like high pH, fish from the Amazon like soft water and low pH. Fish which come from very different environments can not be kept together. SL1 - SL = Standard Length and is the measurement from the tip of the nose to the caudal penduncle (the end of the body where the tail begins). ©This item may not be reproduced without written permission
  17. How to Cultivate Grindal Worms Author: Barrie McKoy For Killies these have to be one of the easiest live foods to feed to growing fry and adults alike. The worms themselves are a size that is halfway in-between both White Worms and Micro Worms. They will stay alive in the tanks for up to 48 hours which is great if you’re taking eggs from your fish and are going away for a few days. I feed Grindals to fry that are about 15 to 20mm long with even those that are only 10mm getting the odd one or two. I was shown this method by Matt Carter and have changed only the food I feed them to Luncheon Sausage. Firstly you need a container to hold the worms; this should have a lid but needs to allow air in, in other words, holes drilled in the top. I’ve used a “click it” container. This is placed in another container. In this case I’ve used an ice cream container to help keep the culture darker. When the Ice Cream lid goes on, I leave one corner open slightly to allow air in and out. I use soil/peat from a small garden in the front of my garage. It has been built up over the last 30 years with top soil and peat from pot plants as well as a few grass clippings. I fill the click it container about half full with this medium and dampen slightly so that the worms don’t simply dry out. I add a starter culture of as many worms as I can realistically find without destroying my original culture and place a small amount of lunchon sausage on the top. Just enough for them to eat over a two day period. I change this with fresh luncheon every two days and wait until the worms are multiplying quickly. They will be clearly seen on the glass. And can be washed into your tanks to be eagerly consumed by your fish. It’s enough to make you feel hungry isn’t it? Barrie McKoy with special thanks to Matt Carter. ©This item may not be reproduced without written permission
  18. Wingless fruitflies Author: Rob Torrens Date: Friday, April 19 2002 These are small (about 3mm), prolific, easily reared and relished by smaller fish, particularly surface feeders. While being called wingless they are probably better described as being stump winged, as they still have wings but they are deformed so that they can’t fly. The fly’s body is soft and floats on the surface, where it can survive for hours. The larvae can be picked out and fed directly (though this is messy and probably involves too much effort for the reward). - Larvae, pupae and adults will live together in the one bottle. - At room temperature the time from egg to adult fly is about 2 weeks. If the temperature is higher the development is accelerated but the higher temperature can encourage bacteria, fungi and mites. The media for raising fruitfly varies, though two of the simplest are: - Ripe banana with a little yeast added, leave this for 2-3 days for fermentation to start, then add the flies. - Add 0.5-1cm of cornmeal/oatmeal (or a mix of the two – the cornmeal seemed to make the culture remain ‘sweeter’ for longer but also went runny very quickly hence the mix of corn and oat meals) to the bottom of the culturing container, pour some boiling water over the mix to get it to gel, allow to cool, then sprinkle over some yeast and sugar. After fermentation has started the flies may be added. I put this media into the bottom of a medium sized plastic container, let it ferment for a couple of days and then introduce the fruitflies. The larva live in the media and will then crawl up the sides to pupate and then the adult flies congregate on the sides and lid. Regarding the lid – I normally just cut a hole in the top and fill the hole with a plug of filter wool or cotton wool. Make sure that the plug is quite dense so that larva want crawl through it. This is less effort than carfeully gluing a bit of stocking over the hole. Just poking holes in the lid causes problems – though the adults may not be able to escape through small holes the larva can and end up pupating on the outside of the container. Points to note: When the culture is first prepared, before adding the flies, there may be a build up of alcoholic fumes too strong for the flies. After 3-5 days this is no longer a problem.Cultures shouldn’t be exposed to direct sunlight.New cultures should be started every 3-4 weeks to assure a continuous supply.I keep the cultures in the hot water cupboard so that their live cycle is speed up (so far I haven’t had problems with mites, fungus etc).The mix will start to sour and smell after a while, this is probably a good time to start a new culture before all the adults die.If the mix becomes too runny but in a piece of dry bread to soak up the excess moisture (the adults seem to have a death wish and will drown themselves if the mix is too runny. Some people had in a piece of carboard going from the bottom to one of the sides to act as an escape ladder for the adults).As these are small and remain on the surface they are ideal to feed to tetras, hatchet fish, killies and others that I can’t think of at the moment. The way I feed them out is to open the container over the open tank, tap the lid a couple of times on the side of the tank and all of the adults that were holding onto the lid are now on the water surface. While you’re doing this your other hand (holding the container) should still be above the tank so that any escapees end up in the tank. Put the lid back on the container and proceed to evict any stray flies that may have ended up in the tank cross bracing etc. ©This item may not be reproduced without written permission
  19. Lumbriculus variegatus – Blackworms Author: Simon Check First published in Aquarium World Aug 2011 Few fish can resist a wriggling worm as part of their diet. Blackworms are ideal live foods for your fish for the fact that the worms are easy to grow and will survive almost indefinatley in your tank until eaten, thus preventing pollution due to decomposition. Although not bred or found often in New Zealand, Lumbriculus worms are actually quite common. They resemble Tubifex worms in appearance but this species of worms live in shallow water marshes, ponds, and swamps, feeding on microorganisms and organic material, unlike tubifex which prefer deeper less sanitary conditions. Reproduction is by division of the worms many (up to 150-200) segments, where each segment is able to develop into a fully functional individual. Sexual reproduction does occur, but is not very common. They can reach to approx 10cm in length when fully extended. Lumbriculus uses its head to forage in sediments and debris, while its tail end, specialized for gas exchange, often projects upwards, When disturbed they will quickly contract itself into the sediment or swim away in a corkscrew fashion. Photo: Simon Check Breeding Blackworms First task here is to acquire some blackworms. You can either ask other fish keepers if they can spare a few or you can search for some yourself. The most common way to find them is in the sediment or gravel in the bottom of Garden ponds. The image above is of an abundance of blackworms living in a Trout rearing pond ( the supply of food for the worms is in abundance due to the public feeding of trout at the viewing window). Most ponds and or streams/ditches have blackworms, you just need to find them. Favorite micro habitats include layers of decomposing leaves, submerged rotting logs, or sediments at the base of emergent vegetation To breed these worms all you need is a small glass tank or container ( glass so you can view from the side), an air pump and air powered filter, Turkey baster/Syringe, some gravel and clean chlorine free water. My setup is just a basic 20 X 20 X 20 cube tank, with a few cm of gravel. A cheap air powered sponge filter to keep the waste levels down is situated in the middle of the tank and the worms are simply introduced. There is conflicting information about as to the temperature that the tank should be kept at, but for best results I keep mine around 18 degrees Celsius. The worms will certainly survive much cooler temps but growth rates are dramatically reduced with the reduced temperatures. Simply add the gravel and half fill the tank with chlorine free water. Introduce the worms and add a small bit of decaying leaves and leave them for a day or two before feeding. This addition of the decaying leaves initially and after water changes in my experience has resulted in the reproduction rate initially increasing faster than without. I do not feed for the first day as I allow the worms to acclimatise to the changes and avoid polluting the tank. Feeding is simple. I feed mine fish food ( a handy use for that cheap supermarket fish flake that the mother in law gave you for Christmas). I just sprinkle a pinch in every few days and do not feed again until I cannot see the flake on the bottom. The worms live in the gravel and they can be seen congregating around the fish food. Maintenance is minimal and involves just water changes and if the culturing is going well they will eventually require a full clean out as they produce a fair amount of waste which will foul the water. Simply gravel vac the tank into a bucket and don’t worry about sucking up the worms. You retrieve them from the bucket once the contents of the syphoned bucket is settled using a turkey baster or large syringe. The worms will just bunch up into a ball and are easy picking. Rinse them with fresh water and feed out half of them and then replace the remaining half in the worm tank. Collection of worms to feed out between tank cleanups is as simple as stirring the gravel up and using a turkey baster/syringe to suck the worms up as they wriggle about in the water. Most fish will snap these up before they can escape. Apisto’s and Corydora love them. My Geophagus love them. Haven’t had a fish that doesn’t yet. Collected worms ready for feeding out. Photo: Simon Check © This item may not be reproduced without written permission
  20. Kelly

    Filters

    Filters - Basic Guide Author: Adrienne Dodge Choosing a filter There are many varieties and brands of filter available to the fish keeper. The type of filter most suitable for you and your tank will depend a lot on the tank size and the type of fish you keep. It is recommended that when purchasing a filter you choose one that will turn the volume of water in your tank over 4 – 6 times per hour ie if you have a 40 litre tank, choose a filter that has a flow rate between 160 – 600 litres per hour. There are references below to Biological, Mechanical and Chemical filtration. This is covered under ‘Cycling your tank’. Under gravel or Undergravel filter These filters are the lowest maintenance and are generally the cheapest to keep running however they do not always work well in planted tanks as unless you have deep enough substrate the roots can eventually block the plastic grates. An under gravel filter is a filter where water is drawn through the gravel - the gravel becomes your filter media. When you purchase an under gravel filter you are purchasing a plastic grate (filter plate) which keeps the gravel off the bottom of the tank, lift tubes to deliver the water and a small length of plastic airline. NB – you will also need to purchase, as a separate item, an air pump, some more airline and a check valve. The under gravel filter works by the air pump drawing water through the gravel (which acts as a mechanical and biological filter), up through the vertical pipes (called airlifts) and into the tank. As the water is moved out of the lift tube it is replaced with water from under the filter plate – this water has been pulled through the gravel (mechanical filtration) which has caught any free-floating waste particles. The gravel, filter plate, tank bottom and lift tubes all provide a bed for bacteria (biological filtration). With an under gravel filter you do not have to change your filter media but you will need to clean the gravel regularly. Using a gravel vacuum clean approximately 1/4 to 1/3 of the gravel every time you do your weekly water change. If you do not the debris is likely to collect in the holes in your plastic grate. These will slowly block and eventually stop the filter from working. Internal filters Internal power filters have a small water pump on top of a narrow box containing a sponge and sometimes other filter media. These sit within the aquarium. They are normally placed in a rear corner of the tank with the outlet just below the surface. Some tanks come with fitted internal filters. Water is sucked in at the bottom of the filter and is drawn through a coarse sponge, trapping debris. The sponges contain what is often referred to as ‘good bacteria’ which converts nasties such as ammonia to nitrite and nitrite to nitrate (see Cycling your Tank). Every 4 weeks, or when you notice the flow of water being pushed out of your filter reducing, the sponge needs to be rinsed in old tank water to remove the debris (syphon out some tank water and rise the sponge in this). If your sponge becomes blocked the filter will not remove as much waste and a slow running filter may also reduce the amount of oxygen in your tank. Do not rinse your sponge under the tap as ‘good bacteria’ will be killed off by the chloride in your tap water. Internal filters are fine for basic use but until recently most do not have much room for media inside them. There are models now available with room for more media than a basic sponge. They are cheap and easy to maintain on lightly stocked tanks External filters An external filter sits outside the tank, normally in a cabinet below. Water is sucked out the tank and into the filter, where it passes through the media, before being returned to the tank.. External filters have much more media inside them than internal filters, so they tend not to need cleaning quite as often. They are also much more versatile, and there is a lot of specialist media you can add to them to improve the quality of your water. If purchasing an external filter consider one with a self-priming mechanism; a device which draws water from the tank into the filer so it can start to pump the water back in to the tank. This makes starting your canister filter easier. © This item may not be reproduced without written permission
  21. Setting up a Tank - Basic Guide Author: Adrienne Dodge Must have equipment – Tank Filter Water Conditioner/s (if required in your area) Fish Food Net Gravel cleaner/siphon Bucket Extras Heater for tropical fish Gravel/stones Plants – live or plastic Lighting Decorations Air pump and airline Test Kit Think of your fish as pets and give them good care and attention. To keep the water clean and healthy care must be taken not to overfeed the fish or put too many fish in the tank. It also means changing 25 – 30% of the water once a week, and cleaning the gravel bed and filter, and wiping any algae off the tank glass and ornaments. If you have plants they will also require tidying/trimming. While this may sound like a lot it really only takes about 30 minutes. CHOOSING YOUR AQUARIUM There are many different brands and styles of aquarium available ranging from small glass square or rectangular tanks with glass lids to large tanks with built in filters and lighting. Before you choose the style you want you need to consider what sort of fish you want to keep. The myth that fish only grow to the size of the tank is wrong; if you look after your fish well and give it good food, clean water and room to swim, it will grow to its full potential. As well as branded aquariums and stands, many glaziers will make aquariums to your specifications so you can have one built to fit a particular space. SETTING UP YOUR AQUARIUM Handle your tank with care. Never attempt to move a full or partly full aquarium. Make sure you have dry hands and always carry an aquarium from underneath, supporting the base at all times. Preparing your tank Using a clean, damp cloth wipe down both the inside and outside of your tank. Never use soap or household cleaners on your tank. Choose A Location If you have chosen an aquarium that comes without a stand, ensure that you place it on a surface that is strong enough to support its total weight. An aquarium that is filled with water and has enough gravel to cover its base sufficiently weighs approximately 5.5 kilograms per 4 litres of water. Always place it on a flat, level surface and place a piece of polystyrene at least 5mm thick between the stand and the tank base. Ensure you have a power source near by. Never place it in direct sunlight, as full or even partial sunlight will cause excessive algae growth. Adding gravel, plants and decorations Rinse your gravel well in a bucket of water and then add to the tank, slope it gradually down toward the front of your aquarium. Rinse and then place any rocks or decorations in the tank. Ensure rocks can not fall down and hit the glass sides of the tank. Filling your Aquarium Place a saucer or clean plastic bag on the tank gravel. Gradually pour the water on top of it. The stream of water will gently deflect without moving the gravel. Always fill your aquarium with water at room temperature. Ensure you treat your water with a de-chlorinator - if you have chlorinated water in your area - before you add it. When your tank is about half full - if you are putting plants in - now is the time to add them. Place higher growing plants to the sides and back of tank, lower growing ones at the front. Continue filling your tank to within 1cm of the top rim. At some stage of the filling process you will need to add your filter – this depends on the type of filter you have chosen to use. The same applies to a heater if you are going to be keeping tropical fish. Do not turn these on until your tank is full. ©This item may not be reproduced without written permission
  22. Aquarium Filtration Author: Warren Stilwell First published in Aquarium World November 2001 There have been many articles written about filtration. Most describe the different types of filtration only. The following information is designed to help you decide which is the best filter for your aquarium. Also covered will be materials and construction methods that work well and cheaply. There are five main types of filter system commonly used: Undergravel – A porous plate below the gravel with uplift pipes using air uplift or powerheads to move the water through the gravel. Box – A plastic or similar container that lives inside the aquarium that circulates water though some type of media using the air uplift method. External – An external box that sits off the side or back of the aquarium. Usually powered, circulates the water through some type of media and sometimes has a bio-wheel. Canister – An external container with pump and hoses that sucks water out of the aquarium, passes it through some types of media in the canister, then returns the water back to the aquarium. Wet/Dry – A canister or box that either lives above the aquarium with a pump that sucks water out of the aquarium into the filter and flows by gravity back to the aquarium, or below the aquarium using gravity and overflow from the aquarium to the filter and a pump to return the water to the aquarium. The water passes through some types of media in the process. Filtration Types: There are three main filtration types: Mechanical – Media that removes large water-born detritus and particulate type matter from the water. Biological – Bacterial removal / conversion of dissolved toxic waste by-products. Chemical – Media that removes dissolved chemicals from the water by chemical exchange. Purpose of a Filter: Fundamental to the success of a healthy aquarium is the stable aquarium environment made possible by scheduled water changes and filtration. Water changes provide systematic removal of wastes not normally removed by filtration and restoration of a balanced ionic environment. No system exists, despite irresponsible or misinformed claims to the contrary, that can replace water changes. What a filter will do is keep the aquarium environment stable for longer so that water changes need only be made periodically. The time between water changes and the size of the water change will depend entirely on the size of the aquarium, the quantity and size of the occupants, how densely planted the aquarium is and the quality of the filtration system. The next section describes more fully how each filter works, its associated costs and advantages and disadvantages. Improvements: There is a major improvement to be made to the canister filter and the trickle filter. The other types of filter cannot use the improvement due to their construction and the fact they do not have a powerful enough water pump. By fitting a prefilter to the canister and trickle filter it is possible to extend the useful life of the biological media. Most advanced biological media manufacturers recommend the media is partially replaced every six to twelve months. If a suitable prefilter is fitted, the particulate matter that clogs the biological media is removed. Therefore the media does not clog and can be used for many years before replacement is required. An added bonus is the ease of replacing and cleaning the prefilter. There is another major benefit, the organic matter that would normally decompose in the filter for up to a month can easily be removed every few days. The result is less build up of waste products the filter has to process, and the water stays fresher for longer. If water changes are still done regularly the quality of the water will be much higher promoting excellent fish health and happiness. The fish will breed more easily and have healthier fry. Disease risk will be greatly reduced when water quality is high. The type of filter best suited for a prefilter is the pleated cartridge filter used on swimming pools. The cartridge and housing can be purchased complete and is fitted between the pump and filter, or tank outlet and filter. If used on a canister filter another pump must be fitted prior to the cartridge filter, as the canister filter’s pump will not be strong enough on its own. These filters are very easy to change and clean. Simply hosing the cartridge every few days will keep it clean enough. Every 2-3 weeks the cartridge can be emersed in a weak solution of bleach to bring it back to new condition. The cartridge is then rinsed thoroughly and left to dry. The pleated cartridge filter has a typical pore size of 15 microns. This is very small, and will remove all particles that will block biological media. The result is very clean water in the aquarium and much happier fish. Pleated cartridge filters come in many different sizes. A suitable size for cartridge filters is; 1000L/H 12sq feet, 3000L/H 30sq feet, 6000L/H 50sq feet, 12000L/H 75sq feet. The cartridges have a square feet measure (being a US design) and the above mentioned sizes will ensure that standard aquarium pumps will work. If a smaller cartridge is chosen there will be too much back pressure on the pump resulting in reduced water flow. Biological Filtration why have it? In a closed aquarium system, waste products quickly build up to toxic levels. If large daily water changes are performed, or a continuous water change method is used, there is no need for biological filtering as the waste products are always being diluted. Most aquariums however do not receive water changes often enough to keep toxin levels diluted to where they have no effect. A biological filter is used to convert the toxic substances that build up quickly into less toxic substances which can exist at higher concentrations without being harmful to the fish and plants. Ammonia, produced by the metabolism of proteins, is the primary waste product from organic sources. Ammonia and ammonium exist in equilibrium in an aquarium. In aquariums with a PH below 7.0 ammonia is only present in very small quantities, and is mostly ammonium. Ammonium is a relatively non-toxic compound. If the PH is raised above 7.0, ammonium balance will convert to ammonia, becoming toxic. As the PH rises, ammonia becomes more toxic is the pH increases. Biological conversion of ammonia Ammonia is converted first to nitrite, and then to nitrate. Both ammonia and nitrite are very toxic at even low levels (0.25-0.5 PPM at PH 7.2-7.4). Nitrate however is much less toxic and can be easily tolerated at levels of 25-30 PPM by nearly all fish and plants. It is important the level of nitrate is controlled by water changes, plants, or denitrifying filter media. At nitrate levels over 50 PPM, fish suffer, and often die for no reason and many plants have their growth stunted. Nitrosomonas convert ammonia to nitrite, and Nitrobacter nitrite to nitrate. Here is the technical stuff from Seachem’s seagrams. Nitrosomonas are short gram-negative rod of about 0.8 by 1.5µm. They are obligate chemolithotrophs, strictly aerobic, that convert ammonia (as the ammonium ion) to nitrite. Nitrobacter are also short gram-negative rods, about 0.7 by 1.5µm, strictly aerobic, obligate chemolithotrophs, that convert nitrite to nitrate. Both can function between pH 6.5 to 8.5, although the optimum is about pH 7.5 to 8.0. Thiobacillus are short gram-negative rods, about 0.5 by 2µm, strictly autotrophic and facultatively anaerobic. They require reduced sulfur compounds as an energy source, converting them to sulfate, using nitrate as an electron acceptor to form nitrogen gas. Carbon dioxide is their only source of carbon. In the presence of oxygen, they utilize ammonia. They can function anywhere between pH 2 to 10, but the optimum is between pH 6.6 to 7.2. There are several genera of anaerobic bacteria that utilise organic compounds (methanol, sugar, other non-nitrogenous organics) and nitrate, converting the nitrate to nitrogen. Anaerobic bacteria do not exist in an aquarium as the conditions are not present to contain them. Rather aerobic bacteria perform an anaerobic function if oxygen is deficient by obtaining their oxygen from nitrate. Ammonia conversion to nitrite: Acidic conditions: 2NH4 + H2O + 3O2 => 2HNO2 + 2H3O ammonium water oxygen nitrous acid water Under Alkaline Conditions 2NH4 + 4OH + 502 => 4HNO2 + 6H2O ammonia hydroxide oxygen nitrous acid water Nitrite to Nitrate: 2HNO2 + O2 => 2HNO3 nitrous acid oxygen nitric acid Nitrate to Nitrogen: NO3 => NO2 => NO => N2O => N2 nitrate nitrite ammonia ammonia nitrogen ion ion ion dioxide Biological Media Biological media is the substrate that the nitrifying bacteria live on. Technically all parts of an aquarium system can be considered part of the filter, – the glass walls, gravel, pipework, rockwork, plants, and the filter. All these items must be considered as they all have surface area suitable for colonising bacteria. It may be possible that the aquarium contents may work almost completely as the filter. This is the idea behind the Berlin filter method used on Marine Aquariums. Only living rock is the filter in conjunction with a good protein skimmer. Media Surface Area If biological filtration is the only concern, then maximising the surface area of the media is important. Other factors must also be considered however; compacting of the media, channeling of water through it, gas exchange and flow rate. If the media is too fine, it may block up, and also gas exchange may not occur efficiently. If it is too coarse, there may not be enough surface area. Sizing the Filter: When designing a filter, the first thing to consider is how fast the water will travel through the media. For a given cross-section of filter media there is an optimum flow rate. A good guideline is: 1. For very porous media with a large total surface area: 500L/hour for 100mm x 100mm of media. The depth of the media should not exceed 150mm. 2. For open media like bio-balls: 150L/hour for 100mm x 100mm of media. The depth should not exceed 600mm. E.g. using porous media for a flow rate of 6000L/hour: 6000 / 500 = 12, so we need 12 x 100mm x100mm of surface area. If 300mm x 400mm cross-section is used, 150mm deep, it will house 18L of media (300x400x150 / 1000000 = 18L). This is a lot of media, so the depth can be adjusted to reduce the amount of media to suit the size of the aquarium and the biological load. If a relatively efficient media were used, e.g. Siporax, 18L would suit an aquarium up to 3600L going by the manufacturer’s specifications. 6000L/hour suits an aquarium of 1200-1800L, so only 9L of substrate is required, dropping the depth of media to 75mm. The media chosen often has an optimum number of liters it was designed to filter. Use this information plus experience from your local fish shop or club to help decide if you will need more or less than the manufacturer recommends. From the flow rate required to filter the aquarium (usually between 3-6 times the total tank volume per hour) work out the cross section of filter required. If you are buying a canister filter, these often come with media. Do not choose a filter too small. If in doubt, go one size up. Biological Load The larger the biological load, the more filter media will be required and the more regular and larger the water changes will need to be. More efficient media will reduce the size of the filter for a given biological load. A more efficient filter design will reduce the media requirements also. Trickle filters tend to be amongst the most efficient biological filters. When combined with efficient biological media, a trickle filter can be physically quite small. Media Types – A Comparison Bio Balls Description: There are many types of these. They are all quite similar having an open design with a hard non-porous surface. Usually made from plastic, having lots if spikes or ledges. Usually spherical in shape. Surface Area: Small surface area. Advantages: Does not clog. Has massive open air spaces for oxygen when used in trickle filters. Best-used in trickle filters. Disadvantages: Small surface area requiring a large volume filter. Not good in canister filters. Cost: Very Cheap to Medium Expensive depending on brand. Best Use: Large Trickle Filters, In Filter Sumps Eheim Effisubstrat Description: A whitish synthetic glass-epoxy chip. Air is injected into the substrate as it is made creating microscopic cavities inside of approx 5-50um. Very suitable for bacterial colonisation on a massive scale. Surface Area: Large, approx 450m2 per liter of media Advantages: High Density bacterial colonisation, making the size of the filter small. Very effective in canister filters. Disadvantages Clogs easily, required a good prefilter. May not allow enough air between each chip for maximum efficiency in trickle filters. Medium / High Cost Cost: High, but offset by less required ($35/liter or $125/5 liter) Best Use: Canister filters and trickle filters mix with a small amount of bio-balls. Siporax Description: Sintered glass noodle. Glass is sintered with gas at high temperature and formed into a noodle approx 25mm diameter 30mm long with a large center hole. It is very porous also having perfectly sized areas for bacteria to colonise. Surface Area: Large, approx 210m2 per liter of media. Advantages: Does not clog. Excellent in trickle filters, – has very good gas exchange. Excellent in sump or canister filters. May reduce nitrates in slow flow sump areas. Small amount of media required. Disadvantages: Medium / High Cost, breaks easily if dropped (doesn’t effect performance) Cost: Medium / High Cost ($25-35/ liter depending on amount and type purchased) Best Use: All round good media, excellent in trickle filters and sumps. Hagen Biomax Description: Ceramic Noodle, a little like Siporax, but not as finely porous. Surface Area: Large approx 1350m2 per liter of media. Advantages: Small amount of media required. Does not clog very easily. May reduce nitrates in slow flow sump areas. Disadvantages: Slowly clogs over long period. Breaks if dropped (doesn’t effect performance). Cost: Medium / High Cost ($35-40 / liter) Best Use: In trickle filters, sumps and canister filters, – good in Fluvals Pumice Description: Volcanic pumice, found at many beaches around NZ. Break the pumice up into small pieces ranging from 10mm to 25mm in size. Surface Area: Medium approx 25m2 /liter of media Advantages: Free, reasonable surface area. Disadvantages: May contain heavy metals and silicates. Will need to be very thoroughly washed before use. Silicates may leach into aquarium leading to unwanted algae. Will slowly clog. Cost: Free Best Use: Trickle filters and Canister filters. Seachem Matrix Description: Processed pumice. Seachem has taken pumice, broken it up, smoothed the edges and washed it. It is guaranteed free from heavy metals and silicates. Surface Area: Same as pumice above Advantages: Ready to use, reasonable surface area Disadvantages: Expensive, will slowly clog. Cost: Expensive Best Use: Trickle filters and Canister filters. Gravel: Description: Hard stone, non-leaching aquarium gravel. Surface Area: Low Advantages: Very Cheap (sometimes free). Does not clog easily, and can be cleaned Disadvantages: Lots required, very heavy. Cost: Very Cheap / Free Best Use: Undergravel Filter Only Filter Wool Description: Dacron type filter wool. Surface Area: Low due to being mainly air. Advantages: Relatively cheap, very light. Disadvantages: Clogs quickly, bacteria form about when the media is starting to clog. Cost: Cheap Best Use: Corner filters Chemical filtration is the direct removal of dissolved compounds by adsorption. The most important function of chemical filtration is the removal of nitrogenous organic waste. This is vital, because such waste is both inhibitory to the biological filter and increases the load on the biological filter. It has a secondary function of polishing the water to give it a sparkle. Adsorption Please bear with this section, – it is a little technical, but gives a good insight into how chemical media works in general. Adsorption, the binding of molecules or particles to a surface, must be distinguished from absorption, the filling of pores in a solid. The binding to the surface is usually weak and reversible. Just about anything including the fluid that dissolves or suspends the material of interest is bound, but compounds with color and those that have taste or odor tend to bind strongly. Compounds that contain chromogenic groups (atomic arrangements that vibrate at frequencies in the visible spectrum) very often are strongly adsorbed on activated carbon. Decolourisation can be wonderfully efficient by adsorption and with negligible loss of other materials. The most common industrial adsorbents are activated carbon, silica gel, and alumina, because they present enormous surface areas per unit weight. Activated carbon is produced by roasting organic material to decompose it to granules of carbon – coconut shell, wood, and bone are common sources. Silica gel is a matrix of hydrated silicon dioxide. Alumina is mined or precipitated aluminum oxide and hydroxide. Although activated carbon is a magnificent material for adsorption, its black color persists and adds a grey tinge if even trace amounts are left after treatment; however filter materials with fine pores remove carbon quite well. A surface already heavily contaminated by adsorbates is not likely to have much capacity for additional binding. Freshly prepared activated carbon has a clean surface. Charcoal made from roasting wood differs from activated carbon in that its surface is contaminated by other products, but further heating will drive off these compounds to produce a surface with high adsorptive capacity. Although the carbon atoms and linked carbons are most important for adsorption, the mineral structure contributes to shape and to mechanical strength. Spent activated carbon is regenerated by roasting, but the thermal expansion and contraction eventually disintegrate the structure so some carbon is lost or oxidized. Temperature effects on adsorption are profound, and measurements are usually at a constant temperature. Types of Media Activated Carbon The most familiar chemical adsorbent is activated carbon. Activated carbon should be a little larger than pinhead in size. When washed and dry, it should be dull and not shiny. When placed in water, it should hiss. It should also tend to float at first. Be careful of charcoal, however, because it is dull and floats, but does not hiss. Charcoal is usually very soft, crumbling easily between the fingers and is usually available only in pea-size. Good activated carbon is hard but fragile, feels hard and does not crumble, but fractures under finger pressure. Not all true activated carbons are equivalent. The most common available carbons are economical water purification grades, usually derived from wood or nutshells. These are not bad carbons, but you may wish to seek out some better grades. The best carbons are usually produced from bituminous coal and have high porosity and low density. They should also have low ash content to minimize impact on pH. Most activated carbons need to be thoroughly washed prior to use. Because it is soft it has a tendency to crush a little during shipping and is therefore covered it carbon dust. Rinse in clean before use. All activated carbons release phosphate, despite claims to the contrary, and only those that release the least should be selected for marine aquaria. Activated carbon adsorbs a small quantity of ammonia, nitrite and nitrate, but the quantity is quite small. In most aquariums it would take a large bucket of activated carbon to remove enough nitrate to be effective. Its main use is to adsorb organic compounds. These compounds give the water its aged look (yellow). It adsorbs dissolved food, fat, and minute dirt particles. Advantages: Easy to use, Relatively Cheap, quickly polishes the aquarium water. Disadvantages: Must be cleaned before use, has a short life (approx. 1 month), many carbons tend to release the waste products back into the water once saturated, does not specifically target unwanted compounds (often removes fertilisers from planted tanks), releases phosphates into the tanks water when first introduced. Zeolite Zeolites are white, dusty clays, usually sold for removing ammonia from freshwater. They are ineffective in seawater or even freshwater that contains modest amounts of salt. Zeolites are ineffective for removing nitrates. It is often sold in boxes or bags specifically designed for use in aquariums. However, it is quite expensive considering how long it is effective for. Zeolite really only needs to be used when setting up a new aquarium, and then only as a precautionary measure. It is also useful to have a box of it handy just in case you get an ammonia spike in an established tank. It must also be washed prior to use to remove the white dust covering it. Failure to do so will result in a rather cloudy aquarium for a while. Some brands of Kitty litter are zeolite based. The granule size is not perfect for use in aquarium filters however, and it is also very dusty. Advantages: Quickly removes ammonia from tanks with an ammonia spike, useful when setting up a new tank. Disadvantages: Quite expensive, does not last long (about 1 month), must be thoroughly washed prior to use. Aluminum Oxide Aluminum oxide is used to remove phosphates and silicates from the aquarium water. Excess phosphate in an aquarium is the primary cause of most algae outbreaks (combined with nitrates). Can be used in both freshwater and marine aquariums. It helps solve many of the red and brown silica algae problems in marine aquariums. It is relatively expensive, but lasts a long time. Get it in bulk as it is around one third of the price by weight. Most food has high levels of phosphate in it. Uneaten food, decomposing plants and fish waste also contribute strongly to the build-up of phosphates. The build-up usually happens faster than the aquatic plants can remove it. Also, many tap water sources are rich in phosphates. The ideal phosphate level in aquariums should be below 0.1ppm (below the measurement level of most test kits). This will slow algae growth to a level that is easily controllable. In large cichlid aquariums huge amounts of waste are produce, – all rich in phosphate. The eating habits of large fish are also such that they munch their food up leaving small uneaten particles in the water. This is style of aquarium presents the hardest algae free challenge, either requiring very regular large water changes with phosphate free water, or large quantities of phosphate removing media. Advantages: Quickly removes phosphates down to trace level, lasts a long time, does not leach back into the aquarium. Disadvantages: A little pricey, must be added slowly to a large volume of water as a lot of heat is produced initially. Also requires rinsing to remove the white powder deposits from shipping. Other Products There are some products that mix two or more types of media together. Some examples are the Ammo-Carb type products. These have zeolite and activated carbon mixed together. They are excellent for new aquariums as a precautionary measure. They need to be washed prior to use. Nitrazorb An aquarium pharmaceuticals product, it specifically targets nitrate. It is also the first of the filter media listed that can be regenerated. Many of the other filter media previously listed can actually be regenerated, but the method to do it is usually well beyond the capability of the equipment we have around our homes. (E.g. To regenerate activated carbon, it must be baked at over 1000°C in the absence of air). Nitrozorb can be easily regenerated using a slat solution. Advantages: Can be regenerated, is available in a convenient size that suits most aquariums, is relatively well priced considering it can be used multiple times. Disadvantages: Must be regenerated, – however it is an easy task. Purigen This is a synthetic product that performs a similar job to activated carbon – made be Seachem. It is said to have all the advantages of activated carbon, but none of the disadvantages. It adsorbs approximately 3 times as much by volume as activated carbon, taking up much less space in the filter. It can be regenerated many times using a medium strength solution of household bleach (sodium hypochlorite). Experience with the product however has shown a tendency to adsorb some of the compound in plant fertilisers, – something Seachem claims it does not do. The effect is not a problem as purigen only needs to be used for 3-4 days to clean up a tank. It can then be removed or moved to another tank. It starts off white, and turns dark brown when full. Soaking in bleach for 24 hours makes it good as new again. It is quite expensive, but very cheap if you look at price comparisons. A 250g bottle of purigen has about equivalent filtering capacity of a 700-800g activated carbon (depending on the brand). Purigen costs approximately $52.00 for 250g. Activated carbon is about $18.00. However, you can regenerate the purigen many times at about $0.50 each time, so: Purigen $75.00 + 60 x $0.50+ $35.00 (bag) = $140.00 for up to 5 years supply. Carbon $18.00 x 60 = $1080.00 for about 5 years supply based on monthly carbon changes. Purigen is clean, and can be used straight away with only a light rinse. It does not have a container however, and you must purchase a bag from Seachem to house the purigen. Advantages: Is cleaner the activated carbon, can be regenerated many times, required less space than activated carbon. Disadvantages: Requires regeneration, a bag to contain the purigen must also be purchased. The initial purchase is a bit pricey, but look at how much it saves long term. Ion Exchangers Synthetic ion exchangers are useful in freshwater to control ionic balance, remove ammonia, nitrite, and nitrate. In marine water, ion exchangers can remove some nitrite and nitrate, but have no significant effect on ammonia. They can also help to retard ionic imbalance. But, generally, the most useful function of ion exchangers, in both fresh and marine water, is organic removal, and in this they excel. Although not an ion exchange process, this ability of ion exchangers to remove organics is phenomenal and works in both marine and fresh water alike. Ion exchange is best used to treat the incoming tap water if it is on insufficient quality to use unprocessed. It would be a very expensive process to continually use ion exchange to filter aquarium water. Ion exchange resins can be regenerated, but it is a time consuming process due to the large quantity of resin required. The resins are also very expensive. Chemical filtration is the direct removal of dissolved compounds by adsorption. The most important function of chemical filtration is the removal of nitrogenous organic waste. This is vital, because such waste is both inhibitory to the biological filter and increases the load on the biological filter. It has a secondary function of polishing the water to give it a sparkle. Designing your own Trickle Filter This article is intended to help you design your own trickle filter. It is based on 10+ years knowledge and experience in filter building for various different sized and styles of aquarium. Step One – Filter Media The first thing to do is decide on the type or types of media you want to use and what fits your budget. Refer to Aquarium Filtration Part 2 for details on media types (Aquarium World May 2001). The type of filter media directly affects the size of the filter. More expensive high-density media means a much smaller filter due to the greatly increased effective surface area. Step Two – Physical Size of the Filter: For a given cross-section of filter media there is an optimum flow rate: 500L / hour for 100mm x 100mm of media surface area. - For Dense Media the depth should not exceed 150mm. - For Loose Media the depth should not exceed 600mm. This ensures good activity from the colonized bacteria but no risk of the bacteria being washed away. Step Three – Filter Style: There are 2 main styles of trickle filter, a filter tower in a sump and a self-contained trickle filter. Filter Tower This style is basically an open bottomed tower suspended into a sump. The advantage of this type is extra flow can be added through the filter using a circulation pump in the sump. The sump is also a great place to house extra equipment like heaters to leave the main tank free of anything that breaks up the natural look. The sump can also add a significant volume to the system. Self Contained This is a small tank divided into sections with the biological media in the main compartment and optional chemical media in another. The return pump or outlet is in the final stage. Examples later in the article illustrate the filter types better. Trickle filters have their media suspended with water trickling through them so there is a large air contact. The media is not submerged. A Trickle filter is very good at converting ammonia to nitrite and nitrite to nitrate but will not remove nitrate. By adding a wet section to the filter using a high-density media with a relatively slow flow, some denitrification will occur. Siporax is an excellent media for denitrification. A Water Diffuser is required to evenly spread the flow over the entire surface of the media. Step Four – Choose your Style from the following examples: 1. Tower Filter with High Density Media Tank Size: 1200L Flow Rate: 6000L/Hr Media Type: Effisubstrate (top of tower) Siporax (in the bottom area) Surface Area Required: 6000 / 500 = 12 (blocks of 100mm x 100mm) Filter Surface Area: 300mm x 400mm Filter Depth: Effisubstrate (approx 200L tank per liter of Effisubstrate = 6L required. Height = 50mm 0.006m3 /0.4m/0.3m = 0.05m = 50mm) Siporax (approx 200L tank per liter of Siporax = 6L required, so also 50mm depth. The filter is built using 6mm glass. It has a support layer + 50mm of media (Siporax) + a 50mm gap + support layer + 50mm of media (Effisubstrate)+ a gap + diffuser area so approx 300mm tall. 2. Stand Alone Filter with High Density Media Tank Size: 1200L Flow Rate: 6000L/Hr Media Type: Effisubstrate (top of tower) Siporax (in the bottom area) Surface Area Required: 6000 / 500 = 12 (blocks of 100mm x 100mm) Filter Surface Area: 300mm x 400mm Filter Depth: Effisubstrate (approx 200L tank per liter of Effisubstrate = 6L required. Height = 50mm 0.006m3 /0.4m/0.3m = 0.05m = 50mm) Siporax (approx 200L tank per liter of Siporax = 6L required, so also 50mm depth. The filter is built using 6mm glass. It has a support layer + 50mm of media (Siporax) + a 50mm gap + support layer + 50mm of media (Effisubstrate)+ a gap + diffuser area so approx 300mm tall. 3. Stand Alone Filter with Low Density Media Tank Size: 1200L Flow Rate: 6000L/Hr Media Type: Effisubstrate (top of tower) Siporax (in the bottom area) Surface Area Required: 6000 / 500 = 12 (blocks of 100mm x 100mm) Filter Surface Area: 300mm x 400mm Filter Depth: Bio Balls (approx 25L tank per liter of Bio Balls = 48L required. Height = 400mm 0.048m3 /0.4m/0.3m = 0.05m = 400mm) The filter is built using 6mm glass. It has a support layer + 400mm of media (Bio Balls) + a gap between the media + diffuser area so approx 500mm tall. Some of the media is below the water level but most is above. If you need all the media to be above then the filter must be made taller still and the media support raised up. Planted Tanks: If you have CO2 injection on a planted tank the trickle filter needs to be sealed. To do so requires a seal around the top edge of the water diffuser so the CO2 cannot escape. The bottom of the tower or media area must be below the water level also. If the CO2 is trapped inside the media area it must diffuse back into the water to escape. If the media area is not sealed the turbulent water flow over the media will expel the CO2 making it difficult to get the required level in the tank. Mechanical Filtration: If high density media is used a prefilter of approximately 15 microns will extend it’s life by 10+ times. If no prefilter is used, place filter wool approx 50mm thick on top of the filter media. This will catch the worst of the muck. The filter wool will need changing every 2-4 weeks. Assembly: The filter is assembled in the same manner as making an aquarium. Extra strips of glass are required in the media chamber to create an edge for the support to sit on (glued to the side walls). The support can be made from old (or new) undergravel plates. If a stand-alone filter is made, an extra piece of glass to set the water level (a weir) is required. A suitably sized area needs to be made for the pump. This area has to be deep enough so the pump does not suck air. You now have the information to make your own trickle filter without having to guess the physical dimensions. For larger tanks this is a much cheaper method of filtration. It’s also a lot easier to clean than canister type filters. Its only real drawback is the size and weight. Data Sources / Acknowledgements Discus Health Dieter Untergasser ISBN: 0-86622-168-9 Seachem: Seagram Data Sheets Davies Pumps: Technical Data Sheet Spa Pumps: Technical Data Sheet Marine Invertebrates: Martyn Haywood / Sue Wells ISBN 1-56465-139-8 © This item may not be reproduced without written permission
  23. GlassThicknessCE.xls Calculating Glass Thickness for Aquariums Author: Warren Stilwell First published in Aquarium World February 2001 Introduction For too long now the thickness of glass required to make an aquarium has been a mystery. There are various tables and guidelines that specify the thickness of glass for a given size aquarium. The major drawback with the information is there is no indication of safety factors for the specified glass thickness or any indication of how the suggested thickness was calculated. This article is intended to help those people who are serious about aquarium design to calculate the correct thickness of glass based on what is an acceptable safety factor for them. There are other points to consider as well as the formula that will also be covered. This information is intended as a guide only, and is in no way a guaranteed formula for success. It is based solely on proven stress calculation methods and does not account for manufacturing defects or construction faults. The Nature of Glass Glass is a totally brittle substance. It will bend a very small amount, but has no capacity like most metals to deform. It will bend to a point and then break. It is this bending stress that is the focus for calculating the thickness. Glass also has a wide variability in strength. Testing samples of uniform manufacture has proved this (see specifications for glass, – Tensile Strength 19.3 to 28.4MPa). Glass is weak in tension, is elastic up to its breaking point, and has no ductility. It is not capable of being permanently deformed, and does not give any pre-warning of impending failure by showing a permanent set after an excessive load has been removed. An important characteristic is its ability to carry an impulse load approximately twice its rated load (i.e. banging the aquarium with your hand quite hard). This is inevitably what saves many aquariums when they are accidentally knocked. The variability of the strength of glass due to limitations of the manufacturing process means a suitable safety factor must be used when calculating glass thickness. The factor commonly used is 3.8. While not a perfect guarantee, it will remove all risk bar that of damaged or very poor quality glass. The main damage that will cause failures is scratches and chips. Also a point load on the glass surface will cause it to fail. For this reason a soft packer like polystyrene is used under aquariums to stop the point loading of dirt and grit. Also when manufacturing an aquarium, the joining compound (commonly silicone) must have a minimum thickness (0.5-1mm) to allow for irregularities along the glass edge. When glass is cut it is not flat along its edge unless it has been specially ground. It is possible to use a lower safety factor if the glass is of excellent quality and has no internal stress. It is at the designers risk however to lower the safety factor. Toughened glass is considerably stronger than standard glass. It cannot however be cut. If toughened glass is to be used it must first be cut to size, have its edges finished and then be send away for toughening. The thermal resistance properties of glass are also improved by toughening. Standard 6mm glass will rupture if plunged into water at 21°C if the temperature of the glass is more than 55°C hotter or colder. Toughened glass will rupture at approximately 250°C difference. Toughened glass also has a tensile strength greater than 5 times that of standard glass. Standard glass has a very important advantage when used on aquariums. It tends to fail in a non-spectacular manner, – typically a vertical or diagonal crack. Toughened glass however will fail completely, much like the old style car windscreen (100% shattering). Glass has a much lower coefficient of linear expansion that most metals. This is important if a metal frame is to be used as part of the structure of the aquarium. If so, the aquarium should be built and stored at a temperature similar to that which it will run at. The length of the aquarium will decide how much elasticity will need to be accommodated by the sealing compound used. Silicone Rubber is the most common sealing compound today. The thickness of the sealing layer needs to be changed as the seal length increases. A general rule of thumb is to allow 2-3mm per meter of joint length. This allows the silicone to take up the stretching forces between the glass and steel. Glass Physical Characteristics: Density: approx 2.5 at 21°C Coefficient of linear expansion: 86 x 10-7m/°C Softening Point: 730°C Modulus of Elasticity: 69GPa (69 x 109 Pa) Poisson’s ratio: Float Glass 0.22 to 0.23 Compressive Strength: 25mm Cube: 248MPa (248 x 106 Pa) Tensile Strength: 19.3 to 28.4MPa for sustained loading Tensile Strength (toughened glass): 175MPa. Design Considerations: The calculations that follow expect the glass to be supported around its perimeter on all four sides. The calculation is the same regardless of whether the perimeter join is in compression or tension. Typical all glass aquariums have all their joins in either tension or shear or both. This method of construction relies 100% on the strength of the silicone holding it together, and is also the weakest join type when using silicone. Steel frame aquariums have the silicone under compression. The silicone is not required to have any strength for this type of aquarium and serves only as a sealer and packer. The thickness of the bottom glass is covered by the second set of calculations, but does not cover an aquarium which has a bottom glass that is well supported from below the aquarium in an even uniform manner. The surface must be very level. On very large aquariums this can be difficult to achieve and self-leveling filler may be needed between the polystyrene and the base. This should be applied just prior to fitting the aquarium to the base so that the aquarium’s weight levels out imperfections. Significant time must be allowed for the filler to fully cure before the aquarium is filled. If the bottom glass is only to be supported by all four edges then use the second set of calculations. The same thickness glass can be used on a uniformly supported bottom as well and this will significantly improve the safety factor. If the aquarium is to be supported from below in a uniform distributed manor, then the same thickness glass that is used for the largest side panel may be used. To do so requires the supporting base to support part of the load so therefore it must be VERY strong. NOTE: The calculations only consider the water to the top edge of the glass. If the glass is a window below the surface then it is outside the scope of this article. Calculations Terms Used: Length in mm (L): The length of the aquarium. Width in mm (W): The width of the aquarium from front to back. Height in mm (H): The overall depth of water that is in contact with the glass, but does not exceed its upper edge. Thickness in mm (t): The thickness of the Glass. Water Pressure (p): The force in Newton’s (N). Allowed Bending Stress (B): Tensile Strength / Safety Factor Modulus of Elasticity (E): Elastic Strength The length to height ratio effects the strength of the glass. The table below lists alpha and beta constants to be used based on with the length to height ratio. Table of Alpha and Beta Constants used in the Calculations For Side Panels For Bottom Panels Ratio of L/H Alpha Beta Alpha Beta 0.5 0.003 0.085 0.666 0.0085 0.1156 1.0 0.022 0.16 0.077 0.453 1.5 0.042 0.26 0.0906 0.5172 2.0 0.056 0.32 0.1017 0.5688 2.5 0.063 0.35 0.111 0.6102 3.0 0.067 0.37 0.1335 0.7134 When the ratio is less than 0.5, use Alpha and Beta values for 0.5. When the ration is greater than 3, use Alpha and Beta values for 3. Note: For bottom panel, use Length to Width ration (L/W). The water pressure (p) is directly proportional to the Height (H) x the force of gravity (approx 10 (9.81 for people who want to be exact)). p = H x 10 in N/mm2 The bending stress allowed (B) is equal to the Tensile Strength of glass / safety factor. B = 19.2 / 3.8 = 5.05N/mm2 (Safety factor = 3.8) Calculations for Front and Side Glass Panels: The thickness of the glass (t) is proportional to the (square root of width factor (beta) x height (H) cubed x 0.00001 / allowable bending stress (B)). so; t = SQR (beta x H3 x 0.00001 / 5.05) in mm. Select beta and alpha from the previous chart based on the length to height ratio. The deflection of the glass is proportional to (alpha x water pressure (p) x 0.000001 x Height4) (Modulus of elasticity (E) x Thickness (t) cubed). Deflection = (Alpha x p x 0.000001 x H4) / (69000 x t3) in mm. Example: (Warren’s new tank) Aquarium Length = 3000mm Aquarium Height = 950mm Safety Factor = 3.8 L/H >3 therefore Beta = 0.37 and Alpha = 0.067 p = 950 x 10 = 9500N/m2 Side Thickness: t = SQR (0.37 x 9503 x 0.00001 / 5.05) = 25.06mm Deflection = (0.067 x 9500 x 0.000001 x 9504) / (69000 x 253) = 0.48mm Calculations for Bottom Glass Panel: There is a small difference when calculating the bottom panel thickness. Beta is now calculated from the Length/Width (where the length L is the larger dimension – therefore L/W is always >=1). The Height is still used to calculate the pressure. Be sure to use the Bottom Panel Alpha/Beta values. The thickness of the bottom glass (t) is proportional to the square root of width factor (beta) x height (H) cubed x 105 / allowable bending stress (B), – the same as the side panels. t = SQR (beta x H3 x 0.00001 / 5.05) in mm Select beta and alpha from the previous chart based on the length to width ratio. The deflection of the glass is proportional to (alpha x water pressure (p) x 10-6 x Height4) / (Modulus of elasticity (E) x Thickness (t)cubed). Deflection = (Alpha x p x 0.000001 x H4) / (69000 x t3) in mm. Example: (Warren’s new tank) Aquarium Length = 3000mm Aquarium Width = 900mm Aquarium Height = 950mm Safety Factor = 3.8 L/W >3 therefore Beta = 0.7134 and Alpha = 0.1335 p = 950 x 10 = 9500N/m2 Bottom Thickness: t = (SQR (0.7134 x 9503 x 0.00001) / 5.05) = 34.8mm Deflection = (0.1335 x 9500 x 0.000001 x 9504) / (69000 x 34.833) = 0.355mm Calculate the required panel thickness and tank safety factor of by downloading the MS Excel Calculator GlassThicknessCE.xls This item may not be reproduced without written permission GlassThicknessCE.xls
  24. Cycling your tank Author: Jennifer Hamlin First published in Aquarium World Magazine November 2011 When getting a new tank, it can be tempting to rush and fill it with fish, but if the filter isn’t properly prepared, a new tank can quickly result in a series of disappointments as the water quality deteriorates and the fish struggle to survive. Fish that live in enclosed aquariums are subject to a buildup of toxic wastes in their environment. The majority of these waste products result from the fish urinating, defecating and breathing in the water where they live. Additional waste products can result from decomposing organic matter in the aquarium such as decaying plants, excess food and dead fish. These waste products have one thing in common, the nitrogen molecule. There are a number of species of beneficial bacteria that process nitrogenous wastes into less toxic chemicals and these bacteria work to our advantage by eliminating waste products so that the aquarium is less toxic for its inhabitants. Aquarium filters have been devised to maximise the space provided for these beneficial bacteria to thrive. This type of filtration is called biological filtration and the initial establishment of bacteria within the biological filter is called cycling the filter and is essential to ensure that the water quality is maintained for the good health of the fish. This is one of the most important principles to understand when keeping fish. The Nitrogen Cycle To understand biological filtration, it is helpful to understand the way in which wastes are processed by bacteria in the aquarium. This process is called the nitrogen cycle. Ammonia is one of the principle chemicals in the nitrogen cycle. Fish produce ammonia as a waste product from the digestion of foods and as a by-product from respiration. Uneaten food, solid waste, plant materials, and other organic items decaying in the tank also produce ammonia. Ammonia is a nitrogen-based compound, and it is extremely toxic to all animals. In an aquarium, ammonia can build up quickly. Even a very small amount of ammonia can be stressful to fish so it is important to remove ammonia from the water before it builds up to toxic levels. In nature, a type of bacteria known as Nitrosomonas thrive on a constant diet of ammonia. In an oxygen-rich environment, Nitrosomonas consume ammonia and converts it into nitrite. Nitrite is also toxic to fish and in the long run tends to be a larger problem than ammonia. Another type of bacteria, Nitrospira (also known as Nitrobacter), will consume the nitrite and convert it to nitrate, a relatively harmless compound that can be used up by plants and algae. It is this partnership between Nitrosomonas and Nitrospira which enables the biological filter to function so that fish can be kept in closed aquarium systems. TIP: note the difference in spelling between nitrite and nitrate. Nitrate is the end product so remember it by thinking that the toxic compounds have been all eaten up – ‘ate’ Nitrosomonas bacteria are found everywhere in oxygen rich environments with sufficient nitrogenous waste; however, in the closed aquarium it takes a while for these bacteria to build up a population that is capable of consuming all the ammonia produced by the fish. The buildup of Nitrospira is even slower since high ammonia levels inhibit its growth. Only when the Nitrosomonas bacteria convert the toxic ammonia to nitrite will the Nitrospira populations be able to grow. While it may only take a few days for the population of Nitrosomonas to grow large enough to control the ammonia levels, the delay in Nitrospira growth means it can be a week or more before nitrite is under control. Once the population of nitrifying bacteria is established, the tank is considered to be ‘cycled’ and as long as the level of waste in the aquarium remains constant, and the bacterial population remains healthy, there should no longer be a build up of toxic ammonia. The tank is now a safe environment for fish to live. The end product of the nitrogen cycle is nitrate. In low concentrations, nitrate will not harm fish and it can actually provide a useful nutrient for aquatic plant growth; however, if there are no plants in the tank to consume the nitrate, simpler plants like algae will begin to grow and can cause a nuisance. Also, high nitrate levels can be stressful for fish so it is important to minimise nitrate buildup by keeping aquatic plants or by doing regular partial water changes. Methods of Cycling When establishing a new tank, it is best not to fully stock the tank until the filter is capable of handling the bioload of waste products. There are several ways to get the biological filter ready to handle a tank full of fish. The main methods include: Adding mature media Seeding the filter with a bacterial culture Fishless cycling Cycling with fish Mature Media One of the best ways to quickly establish a working biological filter is to add mature media from an established filter. In other words, this means taking used filter media (e.g. noodles, sponges or filter wool) and placing it into the new filter so that the bacteria can quickly spread throughout the new filter media and tank. In a stable established tank it is safe to remove a small portion of the biological filter media (no more than a third) and replace it with new media. In no time the bacterial populations will return to normal. When transferring the mature media it is important to keep the bacteria alive so that they will be able to colonise the new filter. The bacteria will start to die off slowly without a constant flow of oxygenated water so it is important to get it into a running filter quickly to get the best benefit. It is helpful to treat the media as you would a live fish – ensure it has oxygen and is kept in mature stable water conditions (use mature tank water and avoid temperature extremes). Aim to place it into the filter as soon as possible to minimise bacterial die off. The new filter can be filled with new media and then the mature media can be added (be sure to add some of the ‘dirty’ water that the filter media was transported in as this will contain bacteria as well). The tank should be able to safely handle a small number of fish with minimal risk of ammonia spikes. When the new tank has had time to settle and all of the new media in the filter has had a chance to build up populations of nitrifying bacteria, more fish can be added slowly to build up the bioload (the amount of waste produced by the tank and its inhabitants). The filter in the picture above has been running for a long time and it is well cycled. It has just been opened and a good amount of brown sludge can be seen. A small portion of the ‘dirty’ media from this filter can be a great way to start up a new filter. Seeding the Filter Seeding the filter is when new media is colonised by adding a culture of nitrifying bacteria. This can be achieved either from adding ‘dirty water’ from a mature tank or by adding a commercial bacterial culture like TLC Smart Start to the new tank water. Once the bacteria have been added to the new media, they must have a supply of nitrogenous waste to consume or they will not survive. Adding a few hardy fish can ensure that these bacteria survive however it is very important to monitor the ammonia and nitrite levels to make sure that the bacteria are able to handle the waste that the fish provide. A number of excellent products are avaialble on the market that offer bacterial cultures that can speed up cycling. TLC Smart Start is one such product. A bottle of this is added to the tank and a full complement of nitrifying bacteria will seed the filter as well as all other surfaces of the tank helping it to get established and avoid toxic levels of ammonia and nitrites. Other tank additives such as Cycle, Seachem Prime and Stress Zyme have some added nitrifying bacteria that can be added on a weekly basis, or whenever water is changed, to help with cycling but they are generally just adding Nitrosomonas bacteria in small quantities so are not as effective at completely seeding the filter. Some can be useful in reducing toxic ammonia levels but this should not be a cure for bad husbandry. Fishless Cycling If starting with completely new media in a new tank, virtually no nitrifying bacteria will exist so a population will need to be established. The first step is to create an ammonia-rich environment that will support the first populations of beneficial bacteria. Ammonia can be supplied by fish living in the tank, or by adding pure household ammonia to a tank that as no fish. In the interests of minimising suffering to the fish who may have to endure toxic levels of ammonia and nitrite, a fishless cycling method is preferred by many experienced fishkeepers. This method also tends to be much faster than cycling with fish since a higher level of ammonia can be added without risking harm to any fish. How To: With the fishless cycling method, no fish are added until the tank is completely cycled. The ammonia levels are created artificially either in the form of adding decaying food, dead fish, dead shrimp or simply by adding a small amount of pure ammonia (without added detergents) from the supermarket. The following steps are carried out: The tank is filled with water and the heater is turned up to 32 degrees. Ammonia is added until the levels are just detectable (up to 4 ppm (mg/L) using a standard aquatic ammonia test kit. The water is tested every day and after a week or so the ammonia levels will begin to drop and the nitrite levels will increase. After a few more days, the nitrite levels will keep rising and eventually it will start to fall and the nitrate levels will begin to increase. Once there is no trace of ammonia or nitrites the temperature can be turned down and a partial water change can be carried out (do not clean the filter or vacuum the gravel). This process will take 7 days to 3 weeks depending on the concentration of ammonia and the careful control of ammonia levels throughout. A small number of fish can be added as soon as the water is tested to be stable for 24 hours (i.e. a suitable temperature and no toxic compounds). The number of fish can gradually be built up over time as bacterial populations adjust to the bioload. Cycling with Fish A new tank and filter can also be cycled with fish using the same principle as the fishless cycling method; however, this method uses the natural ammonia waste products from the fish living in the tank instead of any adding any pure ammonia. In many ways, this method is the least desirable way to cycle the tank since the fish may have to endure very toxic conditions until the nitrifying bacteria have populated the filter sufficiently to handle the bioload. Since the tank is in a state of instability, there are also additional problems that can occur during this process including bacterial bloom or fish diseases. How to: There are a few things to consider when cycling with fish: Only a few fish should be added (depending on the size of the tank) so that the amount of waste product is very low – this will help ensure the ammonia levels do not spike too high and kill all the fish suddenly. Some species of fish are not hardy enough to withstand the harsh conditions of cycling but even for the hardiest species it is not uncommon for fish to die during this process. Oxygen levels must be kept very high since the ammonia will damage the fish’s gills and make it difficult for them to extract oxygen from the water. The fish should not be fed too much and ideally not at all if the ammonia levels have spiked. Very careful monitoring of the ammonia levels will If ammonia levels rise over 4 ppm (mg/L) then steps will need to be taken (such as partial water changes) to reduce toxicity or the fish will die. If conditions get too harsh, chemical filtration like Ammo Chips can be added to absorb excess ammonia and while this can save the fish, it will delay the cycling process. Chemicals like Ammo Lock will temporarily make the ammonia levels safe, but they will not prevent the nitrifying bacteria from utilising it which means toxic nitrite will still be produced. It is important to be aware that the fish will be stressed by rapidly fluctuating tank conditions so make every effort to keep conditions in check. Water Testing For experienced fishkeepers, water testing is something that is carried out if and when there appears to be a problem. Carefully observing the fish’s behaviour can say a lot about the tank’s water stability and an experienced fishkeeper can detect even the most subtle changes in demeanour, activity and appetite. For new or inexperienced fishkeepers, water testing is a way to ensure that the tank is safe for fish to live in and it can help educate about early signs of problems. At its very basic, water testing helps to ensure that the filter is functioning optimally; it also is a way to ensure that the pH, hardness and salinity are as they should be for the species being kept. For some parameters, like ammonia, nitrite and nitrate, it is helpful to test the tank water before doing a water change since the objective is to determine what the fish have been living in and how well the filter is working. For other parameters, like pH, hardness and salinity (for brackish or saltwater tanks), the testing should be carried out on the water that will be introduced to the tank although they can also be carried out on existing tank water if a fluctuation in these values is suspected. Most fish shops offer free water testing for the basic parameters such as ammonia and nitrite but it can be very helpful for a fishkeeper to purchase their own test kit that they can use in the home when needed. Monitoring water chemistry with a home kit is an easy affair. Most test kits provide easy to follow instructions and information about what results should be expected and when to seek help. © This item may not be reproduced without written permission
  25. Cutting Glass Author: Barrie McKoy The cutting of glass is not as hard as a lot of people think the tools that are needed are very basic and safety equipment is probably already in your home. The tools are a straight edge that is not too thick and a “diamantor” cutter and a container of light machine oil. Safety gear is eye protection and rubber gloves. I mentioned a brand in “diamantor” as it’s a cheap but very good cutter that we in my company use almost exclusively. There are other brands and most work well but the “diamantor” is probably the most used cutter in New Zealand. Self oiling cutters are very good and last for years if you look after them but for the price (normally about 5 times the cost) I don’t use them. The cutting wheel lasts no longer than a standard wheel unless it is treated ideally. We use a small jar/tin with an old rag on the bottom and tip enough oil into the container to dampen the rag. Your glass cutter should always be kept in this tin as that keeps the cutting wheel in good condition. Your glass is laid flat on a table or similar that has been covered with a thin blanket so as to “cushion” the glass without allowing the glass to sag into the cover. With a marker pen, measure and mark the first cut on both ends of the glass. Make sure that you are measuring from a good clean edge with no chips on then edges. Place your straight edge on the glass and line it up with the marker pen marks but allow for half the thickness of the cutter. Gently place the cutter against the straight edge so that you can make sure that you have allowed enough room on the marks. Ask someone to help hold the straight edge at one end and with your free hand, hold the “beginning” end. Your cutter should be holding a small amount of oil from the tin. Make a firm steady cut from one end to the other. When starting the cut, start 1 mm in from the starting edge as by starting over the edge can sometimes break the glass and will damage and shorten the life of any cutter. Glass has greater impact strength than steel so the square edge on the edge of the glass will put a small dent in the cutting wheel causing a “miss” in the cut and possible breakage. If your cutter develops a miss, don’t try to use it but instead throw it out as it will cause the glass to break or at best give a less that perfect edge. Make one solid cut and do not go over the cut again. If the cut has small misses in it, join them up. Do not recut the whole cut again. After you have made the cut, its time to break open the glass. You can either place the end of the cutter under the cut and press down evenly on both sides of the glass. Snap the glass as soon as possible after making the cut. If a cut is left too long, the cut goes cold and breakage will often occur. Or you can place a straight edge under the glass and again press down evenly on both sides of the cut. Repeat the above to make your second cut. After the glass has been cut, it would also pay to sand the edges at avoid cutting yourself and to help protect the glass from chipping. Do this by using a sanding block with 180grit “wet and dry” sand paper or greater. Run the sandpaper off the edge of the glass at about a 45deg angle which should create a nice “arris” and look far nicer than a sharp edge. Make sure to vacuum both the blanket and surrounding areas as small sparkles of glass will be almost impossible to see. ©This item may not be reproduced without written permission
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